Vulnerability · Published Sep 6, 2026 · Assigned by curl
CVE-2026-18924HTTP/2 server push UAF
Critical 9.1
In plain English
A critical-severity use-after-free in curl from curl. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 48% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)9.1Critical
Exploit odds (30 days)0.6%top 51.9% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
A flaw in libcurl's handling of HTTP/2 Server Push streams, when the parent handle is set to share connections with other handles, can lead to use-after-free in the cleanup process.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.23 | curl | 8.22.0-r0 | ALPINE-CVE-2026-18924 |
| Alpine:v3.24 | curl | 8.22.0-r0 | ALPINE-CVE-2026-18924 |
| Debian:12 | curl | no fix listed | DEBIAN-CVE-2026-18924 |
| Debian:13 | curl | no fix listed | DEBIAN-CVE-2026-18924 |
| Debian:14 | curl | 8.22.0~rc2-1 | DEBIAN-CVE-2026-18924 |
| Ubuntu:22.04:LTS | curl | 7.81.0-1ubuntu1.29 | USN-8820-1 |
| Ubuntu:22.04:LTS | curl | 7.81.0-1ubuntu1.29 | UBUNTU-CVE-2026-18924 |
| Ubuntu:24.04:LTS | curl | 8.5.0-2ubuntu10.15 | USN-8820-1 |
| Ubuntu:24.04:LTS | curl | 8.5.0-2ubuntu10.15 | UBUNTU-CVE-2026-18924 |
| Ubuntu:26.04:LTS | curl | 8.18.0-1ubuntu2.7 | UBUNTU-CVE-2026-18924 |
| Ubuntu:26.04:LTS | curl | 8.18.0-1ubuntu2.7 | USN-8820-1 |
| Ubuntu:26.10 | curl | 8.20.0-2ubuntu11 | UBUNTU-CVE-2026-18924 |
Affected products (as reported)
Weakness: CWE-416 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H