How severe is CVE-2026-23918?

CVE-2026-23918 has a CVSS 3.1 base score of 8.8 (HIGH). EPSS estimates a 49.7% probability of exploitation in the next 30 days.

CVE-2026-23918: Apache HTTP Server: http2: double free and possible

Description

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.

Severity

CVSS 3.1 · CISA8.8 HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

SSVC · CISA-ADP

Exploitationnone

Automatableno

Technical impacttotal

Affected Products

Vendor	Product	Affected versions
Apache Software Foundation	Apache HTTP Server	2.4.66

References

2 Links

Vendor advisories

https://httpd.apache.org/security/vulnerabilities_24.html

Other references

http://www.openwall.com/lists/oss-security/2026/05/04/19

Record Details

Published

2026-05-04

Last updated

2026-07-15

Assigner (CNA)

apache

Credited to

Bartlomiej Dmitruk, striga.ai; Stanislaw Strzalkowski, isec.pl

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Related Tool Categories

Tool categories that test for or protect against this vulnerability class.

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Fuzzing Binary Exploitation

CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.