Double Free in Apache Http_server
CVE-2026-23918
Double Free and possible RCE vulnerability in Apache HTTP Server with the HTTP/2 protocol. This issue affects Apache HTTP Server: 2.4.66. Users are recommended to upgrade to version 2.4.67, which fixes the issue.
Vulnerability class: Double Free
EPSS: 0.010 (76.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Apache Http_server — versions 2.4.66
- Apache Software Foundation Http Server — versions 2.4.66
Weakness classification (CWE)
Public proof-of-concept exploits
- striga-ai/CVE-2026-23918
- xeloxa/CVE-2026-23918-Apache-H2-PoC
- rhasan-com/CVE-2026-23918
- qassam-315/CVE-2026-23918-Elite-Auditor
- 12lie20/CVE-2026-23918-test
- insomnisec/Detections-CVE-2026-23918
- aa022/CVE-2026-23918-Passive-Audit
- sibersan/apache_audit_cve-2026-23918
- Bencodin/CVE-2026-23918-poc
- alt3kx/CVE-2026-23918
References
- security@apache.org (vendor-advisory, Vendor Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2026-23918?
- CVE-2026-23918 is a high-severity vulnerability in Apache Http_server, classified under Double Free. CVSS score: 8.8/10. Published 2026-05-04.
- How severe is CVE-2026-23918?
- High severity. CVSS v3 base score is 8.8 out of 10.
- Is CVE-2026-23918 known to be exploited?
- 14 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.