When a JavaScript template literal contains consecutive expressions, the context tracking state was not properly reset upon entering a new expression.
We now ensure that template-literal expression entries correctly reset context variables so all subsequent regular expression literals are accurately recognized and escaped.
When "Trailer" headers are sent by a client, the HTTP server internally uses the header values to populate the Request.Trailer map passed to the server handler. Because Request.Trailer is a map, each entry incurs memory overhead. For HTTP/2 servers, a malicious client can exploit this by sending a "Trailer" header that declares a large number of fields, causing the server to allocate a disproportionate amount of memory while bypassing Server.MaxHeaderValueCount and Server.MaxHeaderBytes limits. This exploit is not applicable for HTTP/1 servers, which do not support multiplexing a large number of requests over one TCP connection, and whose Server.MaxHeaderBytes are calculated differently.
On Windows, when the target of Root.Mkdir or Root.MkdirAll is a junction pointing to an empty location, the operation can create a directory at the junction target even when that target is located outside the root. This only applies to operations where the last path component is a junction (path/to/junction, but not path/junction/target).
When http.Transport sends an HTTP/1 CONNECT request with a non-empty Request.Body, it writes the body directly to the connection without framing after the request headers. If the server rejects the CONNECT request with a non-2xx keep-alive response, Transport returns the connection to the idle pool. Because CONNECT requests do not have a request body, the server may interpret the trailing body bytes as a subsequent pipelined HTTP/1.1 request on the connection, leaving the pooled connection desynchronized and causing the next caller that reuses it to read the response to the injected request. In reverse proxies (including httputil.ReverseProxy) that forward CONNECT requests through a shared Transport, this can lead to cross-user response poisoning.
Multiple ECH outer extension references are not permitted under RFC 9849; previously, a client could send a well-crafted packet that could trigger memory exhaustion in the server process by specifying multiple references.
We now reject these as malformed and curb the memory amplification vector as a result.
Parsing a multipart form can bypass memory limits and read an arbitrarily long line into memory when the remaining limit at the start of a part is less than 400 bytes.
When parsing a Range header containing a large number of small ranges, FileServer(FS), ServeContent, and ServeFile(FS) can consume an excessive amount of CPU.
Historically, we have been rather lax about malformed framing-related headers in our HTTP/2 implementation, as they cannot interfere with HTTP/2 framing. However, this makes it possible for our HTTP/2 implementation to forward responses containing such headers to an HTTP/1 client when acting as a reverse proxy. If the HTTP/1 client also does not behave strictly enough, this can result in response smuggling.
A malicious HTTP/2 peer can cause excessive CPU consumption in the client or server by opening a large number of streams and then sending many small SETTINGS frames containing SETTINGS_INITIAL_WINDOW_SIZE values.
The HTTP/2 server can refund connection-level flow control twice for the same data: Once when a client resets a stream (refunding data for any sent-but-unread portion of the stream), and again when a request handler reads the buffered data. A malicious client can exploit this to bypass the configured connection-level flow control limit (MaxReceiveBufferPerConnection). Total buffered data is still limited by the concurrent stream limit and stream-level flow control.
When an HTTP server handler sends a 2xx response to an HTTP/1 CONNECT request and returns without hijacking the connection, the server improperly continues to read and serve requests from the connection. Since a 2xx response to an HTTP/1 CONNECT converts the connection into a tunnel, the server should not treat the connection as continuing to contain HTTP.
The impact of this misbehavior is mostly limited to potential request smuggling, where an intermediate proxy considers the data on the connection to be tunneled and the server considers it to be HTTP.
HTTP/2 servers could end up crashing due to inadvertently modifying its HPACK encoder concurrently. This happens because the server modifies the HPACK encoder from two goroutines without synchronization: one uses the encoder to encode a HEADERS frame as part of a response sent to a client and the other modifies the encoder's table size when handling a SETTINGS frame containing SETTINGS_HEADER_TABLE_SIZE that a client sends. A malicious client can repeatedly send a request while changing the header table size to crash the server.
This PR contains the following updates:
| Package | Type | Update | Change |
|---|---|---|---|
| [go](https://go.dev/) ([source](https://github.com/golang/go)) | toolchain | patch | `1.27.1` → `1.27.2` |
---
### Reset context tracking on consecutive template expressions in html/template
[CVE-2026-94448](https://nvd.nist.gov/vuln/detail/CVE-2026-94448) / [GO-2026-6599](https://pkg.go.dev/vuln/GO-2026-6599)
<details>
<summary>More information</summary>
#### Details
When a JavaScript template literal contains consecutive expressions, the context tracking state was not properly reset upon entering a new expression.
We now ensure that template-literal expression entries correctly reset context variables so all subsequent regular expression literals are accurately recognized and escaped.
#### Severity
Unknown
#### References
- [https://go.dev/cl/839866](https://go.dev/cl/839866)
- [https://go.dev/issue/81821](https://go.dev/issue/81821)
- [https://groups.google.com/g/golang-announce/c/U2fTuyDJznI](https://groups.google.com/g/golang-announce/c/U2fTuyDJznI)
This data is provided by [OSV](https://osv.dev/vulnerability/GO-2026-6599) and the [Go Vulnerability Database](https://github.com/golang/vulndb) ([CC-BY 4.0](https://github.com/golang/vulndb#license)).
</details>
---
### Recognize yield as regexp preceder keyword in html/template
[CVE-2026-97030](https://nvd.nist.gov/vuln/detail/CVE-2026-97030) / [GO-2026-6600](https://pkg.go.dev/vuln/GO-2026-6600)
<details>
<summary>More information</summary>
#### Details
A trusted template author may have previously written a valid template wherein the use of the 'yield' keyword would not be correctly escaped.
We now ensure that valid keyword uses are escaped and non-keyword uses are not escaped.
#### Severity
Unknown
#### References
- [https://go.dev/cl/840925](https://go.dev/cl/840925)
- [https://go.dev/issue/81823](https://go.dev/issue/81823)
- [https://groups.google.com/g/golang-announce/c/U2fTuyDJznI](https://groups.google.com/g/golang-announce/c/U2fTuyDJznI)
This data is provided by [OSV](https://osv.dev/vulnerability/GO-2026-6600) and the [Go Vulnerability Database](https://github.com/golang/vulndb) ([CC-BY 4.0](https://github.com/golang/vulndb#license)).
</details>
---
### HTTP/2 server memory exhaustion due to Trailer headers in net/http
[CVE-2026-78659](https://nvd.nist.gov/vuln/detail/CVE-2026-78659) / [GO-2026-6603](https://pkg.go.dev/vuln/GO-2026-6603)
<details>
<summary>More information</summary>
#### Details
When "Trailer" headers are sent by a client, the HTTP server internally uses the header values to populate the Request.Trailer map passed to the server handler. Because Request.Trailer is a map, each entry incurs memory overhead. For HTTP/2 servers, a malicious client can exploit this by sending a "Trailer" header that declares a large number of fields, causing the server to allocate a disproportionate amount of memory while bypassing Server.MaxHeaderValueCount and Server.MaxHeaderBytes limits. This exploit is not applicable for HTTP/1 servers, which do not support multiplexing a large number of requests over one TCP connection, and whose Server.MaxHeaderBytes are calculated differently.
#### Severity
Unknown
#### References
- [https://go.dev/cl/847185](https://go.dev/cl/847185)
- [https://go.dev/cl/847314](https://go.dev/cl/847314)
- [https://go.dev/issue/81857](https://go.dev/issue/81857)
- [https://groups.google.com/g/golang-announce/c/U2fTuyDJznI](https://groups.google.com/g/golang-announce/c/U2fTuyDJznI)
- [https://groups.google.com/g/golang-announce/c/ZPwCyRUuGBs](https://groups.google.com/g/golang-announce/c/ZPwCyRUuGBs)
This data is provided by [OSV](https://osv.dev/vulnerability/GO-2026-6603) and the [Go Vulnerability Database](https://github.com/golang/vulndb) ([CC-BY 4.0](https://github.com/golang/vulndb#license)).
</details>
---
### Root.Mkdir(All) can follow junctions out of the root on Windows in os
[CVE-2026-56857](https://nvd.nist.gov/vuln/detail/CVE-2026-56857) / [GO-2026-6604](https://pkg.go.dev/vuln/GO-2026-6604)
<details>
<summary>More information</summary>
#### Details
On Windows, when the target of Root.Mkdir or Root.MkdirAll is a junction pointing to an empty location, the operation can create a directory at the junction target even when that target is located outside the root. This only applies to operations where the last path component is a junction (path/to/junction, but not path/junction/target).
#### Severity
Unknown
#### References
- [https://go.dev/cl/847305](https://go.dev/cl/847305)
- [https://go.dev/issue/81739](https://go.dev/issue/81739)
- [https://groups.google.com/g/golang-announce/c/U2fTuyDJznI](https://groups.google.com/g/golang-announce/c/U2fTuyDJznI)
This data is provided by [OSV](https://osv.dev/vulnerability/GO-2026-6604) and the [Go Vulnerability Database](https://github.com/golang/vulndb) ([CC-BY 4.0](https://github.com/golang/vulndb#license)).
</details>
---
### HTTP/1 client connection desynchronization after CONNECT rejection in net/http
[CVE-2026-56866](https://nvd.nist.gov/vuln/detail/CVE-2026-56866) / [GO-2026-6605](https://pkg.go.dev/vuln/GO-2026-6605)
<details>
<summary>More information</summary>
#### Details
When http.Transport sends an HTTP/1 CONNECT request with a non-empty Request.Body, it writes the body directly to the connection without framing after the request headers. If the server rejects the CONNECT request with a non-2xx keep-alive response, Transport returns the connection to the idle pool. Because CONNECT requests do not have a request body, the server may interpret the trailing body bytes as a subsequent pipelined HTTP/1.1 request on the connection, leaving the pooled connection desynchronized and causing the next caller that reuses it to read the response to the injected request. In reverse proxies (including httputil.ReverseProxy) that forward CONNECT requests through a shared Transport, this can lead to cross-user response poisoning.
#### Severity
Unknown
#### References
- [https://go.dev/cl/847306](https://go.dev/cl/847306)
- [https://go.dev/issue/81740](https://go.dev/issue/81740)
- [https://groups.google.com/g/golang-announce/c/U2fTuyDJznI](https://groups.google.com/g/golang-announce/c/U2fTuyDJznI)
This data is provided by [OSV](https://osv.dev/vulnerability/GO-2026-6605) and the [Go Vulnerability Database](https://github.com/golang/vulndb) ([CC-BY 4.0](https://github.com/golang/vulndb#license)).
</details>
---
### Reject malformed ECH outer extension references in crypto/tls
[CVE-2026-97031](https://nvd.nist.gov/vuln/detail/CVE-2026-97031) / [GO-2026-6607](https://pkg.go.dev/vuln/GO-2026-6607)
<details>
<summary>More information</summary>
#### Details
Multiple ECH outer extension references are not permitted under RFC 9849; previously, a client could send a well-crafted packet that could trigger memory exhaustion in the server process by specifying multiple references.
We now reject these as malformed and curb the memory amplification vector as a result.
#### Severity
Unknown
#### References
- [https://go.dev/cl/847312](https://go.dev/cl/847312)
- [https://go.dev/issue/81855](https://go.dev/issue/81855)
- [https://groups.google.com/g/golang-announce/c/U2fTuyDJznI](https://groups.google.com/g/golang-announce/c/U2fTuyDJznI)
This data is provided by [OSV](https://osv.dev/vulnerability/GO-2026-6607) and the [Go Vulnerability Database](https://github.com/golang/vulndb) ([CC-BY 4.0](https://github.com/golang/vulndb#license)).
</details>
---
### Memory limit bypass when parsing MIME headers in net/textproto, mime/multipart
[CVE-2026-94440](https://nvd.nist.gov/vuln/detail/CVE-2026-94440) / [GO-2026-6608](https://pkg.go.dev/vuln/GO-2026-6608)
<details>
<summary>More information</summary>
#### Details
Parsing a multipart form can bypass memory limits and read an arbitrarily long line into memory when the remaining limit at the start of a part is less than 400 bytes.
#### Severity
Unknown
#### References
- [https://go.dev/cl/847307](https://go.dev/cl/847307)
- [https://go.dev/issue/81741](https://go.dev/issue/81741)
- [https://groups.google.com/g/golang-announce/c/U2fTuyDJznI](https://groups.google.com/g/golang-announce/c/U2fTuyDJznI)
This data is provided by [OSV](https://osv.dev/vulnerability/GO-2026-6608) and the [Go Vulnerability Database](https://github.com/golang/vulndb) ([CC-BY 4.0](https://github.com/golang/vulndb#license)).
</details>
---
### Lack of limit on size of parsed Range headers in net/http
[CVE-2026-78667](https://nvd.nist.gov/vuln/detail/CVE-2026-78667) / [GO-2026-6609](https://pkg.go.dev/vuln/GO-2026-6609)
<details>
<summary>More information</summary>
#### Details
When parsing a Range header containing a large number of small ranges, FileServer(FS), ServeContent, and ServeFile(FS) can consume an excessive amount of CPU.
#### Severity
Unknown
#### References
- [https://go.dev/cl/847309](https://go.dev/cl/847309)
- [https://go.dev/issue/81858](https://go.dev/issue/81858)
- [https://groups.google.com/g/golang-announce/c/U2fTuyDJznI](https://groups.google.com/g/golang-announce/c/U2fTuyDJznI)
This data is provided by [OSV](https://osv.dev/vulnerability/GO-2026-6609) and the [Go Vulnerability Database](https://github.com/golang/vulndb) ([CC-BY 4.0](https://github.com/golang/vulndb#license)).
</details>
---
### HTTP/2 transport accepts malformed framing-related headers in net/http
[CVE-2026-78660](https://nvd.nist.gov/vuln/detail/CVE-2026-78660) / [GO-2026-6610](https://pkg.go.dev/vuln/GO-2026-6610)
<details>
<summary>More information</summary>
#### Details
Historically, we have been rather lax about malformed framing-related headers in our HTTP/2 implementation, as they cannot interfere with HTTP/2 framing. However, this makes it possible for our HTTP/2 implementation to forward responses containing such headers to an HTTP/1 client when acting as a reverse proxy. If the HTTP/1 client also does not behave strictly enough, this can result in response smuggling.
#### Severity
Unknown
#### References
- [https://go.dev/cl/835145](https://go.dev/cl/835145)
- [https://go.dev/cl/836385](https://go.dev/cl/836385)
- [https://go.dev/issue/81115](https://go.dev/issue/81115)
- [https://groups.google.com/g/golang-announce/c/U2fTuyDJznI](https://groups.google.com/g/golang-announce/c/U2fTuyDJznI)
This data is provided by [OSV](https://osv.dev/vulnerability/GO-2026-6610) and the [Go Vulnerability Database](https://github.com/golang/vulndb) ([CC-BY 4.0](https://github.com/golang/vulndb#license)).
</details>
---
### Excessive CPU consumption from repeated initial window changes in net/http
[CVE-2026-78669](https://nvd.nist.gov/vuln/detail/CVE-2026-78669) / [GO-2026-6611](https://pkg.go.dev/vuln/GO-2026-6611)
<details>
<summary>More information</summary>
#### Details
A malicious HTTP/2 peer can cause excessive CPU consumption in the client or server by opening a large number of streams and then sending many small SETTINGS frames containing SETTINGS_INITIAL_WINDOW_SIZE values.
#### Severity
Unknown
#### References
- [https://go.dev/cl/847186](https://go.dev/cl/847186)
- [https://go.dev/cl/847308](https://go.dev/cl/847308)
- [https://go.dev/issue/81742](https://go.dev/issue/81742)
- [https://groups.google.com/g/golang-announce/c/U2fTuyDJznI](https://groups.google.com/g/golang-announce/c/U2fTuyDJznI)
- [https://groups.google.com/g/golang-announce/c/ZPwCyRUuGBs](https://groups.google.com/g/golang-announce/c/ZPwCyRUuGBs)
This data is provided by [OSV](https://osv.dev/vulnerability/GO-2026-6611) and the [Go Vulnerability Database](https://github.com/golang/vulndb) ([CC-BY 4.0](https://github.com/golang/vulndb#license)).
</details>
---
### Double flow control refund on HTTP/2 server streams in net/http
[CVE-2026-78663](https://nvd.nist.gov/vuln/detail/CVE-2026-78663) / [GO-2026-6612](https://pkg.go.dev/vuln/GO-2026-6612)
<details>
<summary>More information</summary>
#### Details
The HTTP/2 server can refund connection-level flow control twice for the same data: Once when a client resets a stream (refunding data for any sent-but-unread portion of the stream), and again when a request handler reads the buffered data. A malicious client can exploit this to bypass the configured connection-level flow control limit (MaxReceiveBufferPerConnection). Total buffered data is still limited by the concurrent stream limit and stream-level flow control.
#### Severity
Unknown
#### References
- [https://go.dev/cl/847187](https://go.dev/cl/847187)
- [https://go.dev/cl/847310](https://go.dev/cl/847310)
- [https://go.dev/issue/81743](https://go.dev/issue/81743)
- [https://groups.google.com/g/golang-announce/c/U2fTuyDJznI](https://groups.google.com/g/golang-announce/c/U2fTuyDJznI)
- [https://groups.google.com/g/golang-announce/c/ZPwCyRUuGBs](https://groups.google.com/g/golang-announce/c/ZPwCyRUuGBs)
This data is provided by [OSV](https://osv.dev/vulnerability/GO-2026-6612) and the [Go Vulnerability Database](https://github.com/golang/vulndb) ([CC-BY 4.0](https://github.com/golang/vulndb#license)).
</details>
---
### HTTP/1 server connection desynchronization after 2xx CONNECT response in net/http
[CVE-2026-94439](https://nvd.nist.gov/vuln/detail/CVE-2026-94439) / [GO-2026-6613](https://pkg.go.dev/vuln/GO-2026-6613)
<details>
<summary>More information</summary>
#### Details
When an HTTP server handler sends a 2xx response to an HTTP/1 CONNECT request and returns without hijacking the connection, the server improperly continues to read and serve requests from the connection. Since a 2xx response to an HTTP/1 CONNECT converts the connection into a tunnel, the server should not treat the connection as continuing to contain HTTP.
The impact of this misbehavior is mostly limited to potential request smuggling, where an intermediate proxy considers the data on the connection to be tunneled and the server considers it to be HTTP.
#### Severity
Unknown
#### References
- [https://go.dev/cl/847311](https://go.dev/cl/847311)
- [https://go.dev/issue/81744](https://go.dev/issue/81744)
- [https://groups.google.com/g/golang-announce/c/U2fTuyDJznI](https://groups.google.com/g/golang-announce/c/U2fTuyDJznI)
This data is provided by [OSV](https://osv.dev/vulnerability/GO-2026-6613) and the [Go Vulnerability Database](https://github.com/golang/vulndb) ([CC-BY 4.0](https://github.com/golang/vulndb#license)).
</details>
---
### HTTP/2 server crash due to HPACK encoder race in net/http
[CVE-2026-97032](https://nvd.nist.gov/vuln/detail/CVE-2026-97032) / [GO-2026-6617](https://pkg.go.dev/vuln/GO-2026-6617)
<details>
<summary>More information</summary>
#### Details
HTTP/2 servers could end up crashing due to inadvertently modifying its HPACK encoder concurrently. This happens because the server modifies the HPACK encoder from two goroutines without synchronization: one uses the encoder to encode a HEADERS frame as part of a response sent to a client and the other modifies the encoder's table size when handling a SETTINGS frame containing SETTINGS_HEADER_TABLE_SIZE that a client sends. A malicious client can repeatedly send a request while changing the header table size to crash the server.
#### Severity
Unknown
#### References
- [https://go.dev/cl/847188](https://go.dev/cl/847188)
- [https://go.dev/cl/847313](https://go.dev/cl/847313)
- [https://go.dev/issue/81867](https://go.dev/issue/81867)
- [https://groups.google.com/g/golang-announce/c/U2fTuyDJznI](https://groups.google.com/g/golang-announce/c/U2fTuyDJznI)
- [https://groups.google.com/g/golang-announce/c/ZPwCyRUuGBs](https://groups.google.com/g/golang-announce/c/ZPwCyRUuGBs)
This data is provided by [OSV](https://osv.dev/vulnerability/GO-2026-6617) and the [Go Vulnerability Database](https://github.com/golang/vulndb) ([CC-BY 4.0](https://github.com/golang/vulndb#license)).
</details>
---
### Configuration
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♻ **Rebasing**: Whenever PR is behind base branch, or you tick the rebase/retry checkbox.
🔕 **Ignore**: Close this PR and you won't be reminded about this update again.
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changed title from chore(deps): update go toolchain directive to v1.27.2 [security] to chore(deps): update go toolchain directive to v1.27.2 [security] - autoclosed2026-10-09 08:04:13 +00:00
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This PR contains the following updates:
1.27.1→1.27.2Reset context tracking on consecutive template expressions in html/template
CVE-2026-94448 / GO-2026-6599
More information
Details
When a JavaScript template literal contains consecutive expressions, the context tracking state was not properly reset upon entering a new expression.
We now ensure that template-literal expression entries correctly reset context variables so all subsequent regular expression literals are accurately recognized and escaped.
Severity
Unknown
References
This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).
Recognize yield as regexp preceder keyword in html/template
CVE-2026-97030 / GO-2026-6600
More information
Details
A trusted template author may have previously written a valid template wherein the use of the 'yield' keyword would not be correctly escaped.
We now ensure that valid keyword uses are escaped and non-keyword uses are not escaped.
Severity
Unknown
References
This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).
HTTP/2 server memory exhaustion due to Trailer headers in net/http
CVE-2026-78659 / GO-2026-6603
More information
Details
When "Trailer" headers are sent by a client, the HTTP server internally uses the header values to populate the Request.Trailer map passed to the server handler. Because Request.Trailer is a map, each entry incurs memory overhead. For HTTP/2 servers, a malicious client can exploit this by sending a "Trailer" header that declares a large number of fields, causing the server to allocate a disproportionate amount of memory while bypassing Server.MaxHeaderValueCount and Server.MaxHeaderBytes limits. This exploit is not applicable for HTTP/1 servers, which do not support multiplexing a large number of requests over one TCP connection, and whose Server.MaxHeaderBytes are calculated differently.
Severity
Unknown
References
This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).
Root.Mkdir(All) can follow junctions out of the root on Windows in os
CVE-2026-56857 / GO-2026-6604
More information
Details
On Windows, when the target of Root.Mkdir or Root.MkdirAll is a junction pointing to an empty location, the operation can create a directory at the junction target even when that target is located outside the root. This only applies to operations where the last path component is a junction (path/to/junction, but not path/junction/target).
Severity
Unknown
References
This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).
HTTP/1 client connection desynchronization after CONNECT rejection in net/http
CVE-2026-56866 / GO-2026-6605
More information
Details
When http.Transport sends an HTTP/1 CONNECT request with a non-empty Request.Body, it writes the body directly to the connection without framing after the request headers. If the server rejects the CONNECT request with a non-2xx keep-alive response, Transport returns the connection to the idle pool. Because CONNECT requests do not have a request body, the server may interpret the trailing body bytes as a subsequent pipelined HTTP/1.1 request on the connection, leaving the pooled connection desynchronized and causing the next caller that reuses it to read the response to the injected request. In reverse proxies (including httputil.ReverseProxy) that forward CONNECT requests through a shared Transport, this can lead to cross-user response poisoning.
Severity
Unknown
References
This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).
Reject malformed ECH outer extension references in crypto/tls
CVE-2026-97031 / GO-2026-6607
More information
Details
Multiple ECH outer extension references are not permitted under RFC 9849; previously, a client could send a well-crafted packet that could trigger memory exhaustion in the server process by specifying multiple references.
We now reject these as malformed and curb the memory amplification vector as a result.
Severity
Unknown
References
This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).
Memory limit bypass when parsing MIME headers in net/textproto, mime/multipart
CVE-2026-94440 / GO-2026-6608
More information
Details
Parsing a multipart form can bypass memory limits and read an arbitrarily long line into memory when the remaining limit at the start of a part is less than 400 bytes.
Severity
Unknown
References
This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).
Lack of limit on size of parsed Range headers in net/http
CVE-2026-78667 / GO-2026-6609
More information
Details
When parsing a Range header containing a large number of small ranges, FileServer(FS), ServeContent, and ServeFile(FS) can consume an excessive amount of CPU.
Severity
Unknown
References
This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).
HTTP/2 transport accepts malformed framing-related headers in net/http
CVE-2026-78660 / GO-2026-6610
More information
Details
Historically, we have been rather lax about malformed framing-related headers in our HTTP/2 implementation, as they cannot interfere with HTTP/2 framing. However, this makes it possible for our HTTP/2 implementation to forward responses containing such headers to an HTTP/1 client when acting as a reverse proxy. If the HTTP/1 client also does not behave strictly enough, this can result in response smuggling.
Severity
Unknown
References
This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).
Excessive CPU consumption from repeated initial window changes in net/http
CVE-2026-78669 / GO-2026-6611
More information
Details
A malicious HTTP/2 peer can cause excessive CPU consumption in the client or server by opening a large number of streams and then sending many small SETTINGS frames containing SETTINGS_INITIAL_WINDOW_SIZE values.
Severity
Unknown
References
This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).
Double flow control refund on HTTP/2 server streams in net/http
CVE-2026-78663 / GO-2026-6612
More information
Details
The HTTP/2 server can refund connection-level flow control twice for the same data: Once when a client resets a stream (refunding data for any sent-but-unread portion of the stream), and again when a request handler reads the buffered data. A malicious client can exploit this to bypass the configured connection-level flow control limit (MaxReceiveBufferPerConnection). Total buffered data is still limited by the concurrent stream limit and stream-level flow control.
Severity
Unknown
References
This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).
HTTP/1 server connection desynchronization after 2xx CONNECT response in net/http
CVE-2026-94439 / GO-2026-6613
More information
Details
When an HTTP server handler sends a 2xx response to an HTTP/1 CONNECT request and returns without hijacking the connection, the server improperly continues to read and serve requests from the connection. Since a 2xx response to an HTTP/1 CONNECT converts the connection into a tunnel, the server should not treat the connection as continuing to contain HTTP.
The impact of this misbehavior is mostly limited to potential request smuggling, where an intermediate proxy considers the data on the connection to be tunneled and the server considers it to be HTTP.
Severity
Unknown
References
This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).
HTTP/2 server crash due to HPACK encoder race in net/http
CVE-2026-97032 / GO-2026-6617
More information
Details
HTTP/2 servers could end up crashing due to inadvertently modifying its HPACK encoder concurrently. This happens because the server modifies the HPACK encoder from two goroutines without synchronization: one uses the encoder to encode a HEADERS frame as part of a response sent to a client and the other modifies the encoder's table size when handling a SETTINGS frame containing SETTINGS_HEADER_TABLE_SIZE that a client sends. A malicious client can repeatedly send a request while changing the header table size to crash the server.
Severity
Unknown
References
This data is provided by OSV and the Go Vulnerability Database (CC-BY 4.0).
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chore(deps): update go toolchain directive to v1.27.2 [security]to chore(deps): update go toolchain directive to v1.27.2 [security] - autoclosedPull request closed