Vulnerability record · CVE-2026-63686 · published 1 October 2026

CVE-2026-63686: Apache http server null pointer dereference vulnerability

Apache · Http Server

A NULL pointer dereference in mod_xml2enc in Apache Software Foundation Apache HTTP Server before 2.4.69 on all platforms allows an untrusted backend server to cause a denial of service via a proxied response with a charset whose conversion partially succeeds then fails. Users are recommended to upgrade to version 2.4.69, which fixes this issue.

7.5 CVSS 3.1 High EPSS 0.46% · top 59.6% CWE-476 · NULL pointer dereference

7.5CVSS 3.1 base score

0.46%EPSS exploitation probability, 30 days

NoNot in CISA KEV

1Affected product versions listed by NVD

2References

5 Oct 2026Last modified by NVD

Description

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

Http Server Apache

References

Link	Tags
https://httpd.apache.org/security/vulnerabilities_24.html	Vendor Advisory
http://www.openwall.com/lists/oss-security/2026/10/01/25	Mailing ListThird Party Advisory

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Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-63686), CISA KEV, FIRST EPSS (scores of 2026-11-14). This page is refreshed as NVD updates the record.