CVE-2026-78659
CVE.org · Published
- Record status
- Published
- Identifier year (not publication year)
- 2026
- Source publication
- Source updated
- Imported by cveboard
- Source snapshot
- cve_2026-10-24_midnight_baseline ·
CNA source text (English)
HTTP/2 server memory exhaustion due to Trailer headers in net/http
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.
Scoped product and version facts
Fix information unknown; no fixed version is derived here. Missing information does not prove that no fix exists.
Exploitation unknown; this catalogue does not assess exploitation.
net/http
- Vendor
- Go standard library
- Product
- net/http
- Platforms
- Unknown
- Default status
unaffected- Package
- net/http
- Package collection
- https://pkg.go.dev
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| 0 | affected | semver | 1.26.9 | Unavailable | None listed |
net/http/internal/http2
- Vendor
- Go standard library
- Product
- net/http/internal/http2
- Platforms
- Unknown
- Default status
unaffected- Package
- net/http/internal/http2
- Package collection
- https://pkg.go.dev
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| 1.27.0-0 | affected | semver | 1.27.2 | Unavailable | None listed |
golang.org/x/net/http2
- Vendor
- golang.org/x/net
- Product
- golang.org/x/net/http2
- Platforms
- Unknown
- Default status
unaffected- Package
- golang.org/x/net/http2
- Package collection
- https://pkg.go.dev
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| 0 | affected | semver | 0.60.0 | Unavailable | None listed |