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CVE-2026-56154

Use After Free vulnerability in Apache HTTP Server's mod_rewrite when using lookahead (%{LA-U:HTTP:...}) This issue affects Apache HTTP Server: from 2.4.0 through 2.4.68.

Scores

9.8
CVSS 9.8 out of 10, critical severity.
0.6%
EPSS 0.6% chance of exploitation in the next 30 days.

The facts

Published
1 October 2026
Last changed
5 October 2026
NVD status
Analyzed
Severity
Critical, CVSS 9.8 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness
Affects
  • apache http server
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
0.6% chance of exploitation activity in the next 30 days (percentile 46).

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References