CVE-2022-41717: Excessive memory growth in net/http and golang.org/x/net/http2

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 6.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-12-08 · updated 2026-06-17
Weakness: CWE-770

Description

An attacker can cause excessive memory growth in a Go server accepting HTTP/2 requests. HTTP/2 server connections contain a cache of HTTP header keys sent by the client. While the total number of entries in this cache is capped, an attacker sending very large keys can cause the server to allocate approximately 64 MiB per open connection.

Affected products

Fedoraproject Fedora: 37, 38
Go: before 1.18.9; from 1.19.0 before 1.19.4 — fixed in 1.18.9, 1.19.4
Golang Http2: before 0.4.0 — fixed in 0.4.0
Golang.Org/X/Net: before 0.4.0 — fixed in 0.4.0
Golang.Org/X/Net/Http2: before 0.4.0 — fixed in 0.4.0
Go Stdlib: before 1.18.9; from 1.19.0-0 before 1.19.4 — fixed in 1.18.9, 1.19.4

How to fix

Upgrade to a fixed version: Go 1.18.9, 1.19.4; Golang Http2 0.4.0; Golang.Org/X/Net 0.4.0; Golang.Org/X/Net/Http2 0.4.0; Go Stdlib 1.18.9, 1.19.4. Check the vendor advisory for mitigations.

References

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