Vulnerability · Published Oct 1, 2026 · Assigned by apache
CVE-2026-57941Apache HTTP Server: mod_http2 use-after-free / wild write via shared session->bbtmp re-entrancy
Critical 9.8
In plain English
A critical-severity use-after-free in Apache HTTP Server from Apache Software Foundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 47% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)9.8Critical
Exploit odds (30 days)0.6%top 52.5% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Use After Free vulnerability in Apache HTTP Server's mod_http2 via shared session->bbtmp re-entrancy This issue affects Apache HTTP Server: from 2.4.0 through 2.4.68.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.21 | apache2 | 2.4.69-r0 | ALPINE-CVE-2026-57941 |
| Alpine:v3.22 | apache2 | 2.4.69-r0 | ALPINE-CVE-2026-57941 |
| Alpine:v3.23 | apache2 | 2.4.69-r0 | ALPINE-CVE-2026-57941 |
| Alpine:v3.24 | apache2 | 2.4.69-r0 | ALPINE-CVE-2026-57941 |
| Debian:12 | apache2 | no fix listed | DEBIAN-CVE-2026-57941 |
| Debian:13 | apache2 | 2.4.69-1~deb13u1 | DEBIAN-CVE-2026-57941 |
| Debian:14 | apache2 | 2.4.69-1 | DEBIAN-CVE-2026-57941 |
| Ubuntu:22.04:LTS | apache2 | 2.4.52-1ubuntu4.24 | UBUNTU-CVE-2026-57941 |
| Ubuntu:22.04:LTS | apache2 | 2.4.52-1ubuntu4.24 | USN-8898-1 |
| Ubuntu:24.04:LTS | apache2 | 2.4.58-1ubuntu8.16 | UBUNTU-CVE-2026-57941 |
| Ubuntu:24.04:LTS | apache2 | 2.4.58-1ubuntu8.16 | USN-8898-1 |
| Ubuntu:26.04:LTS | apache2 | 2.4.66-2ubuntu2.5 | UBUNTU-CVE-2026-57941 |
| Ubuntu:26.04:LTS | apache2 | 2.4.66-2ubuntu2.5 | USN-8898-1 |
| Ubuntu:26.10 | apache2 | no fix listed | UBUNTU-CVE-2026-57941 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Apache Software Foundation | Apache HTTP Server | 2.4.0 – through 2.4.68 |
Weakness: CWE-416 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H