Buffer overflow in Apache Http_server

CVE-2026-42536

Heap-based Buffer Overflow vulnerability in Apache HTTP Server with mod_xml2enc, xml2StartParse, and untrusted content This issue affects Apache HTTP Server: from 2.4.0 through 2.4.67. Users are recommended to upgrade to version 2.4.68…

Vulnerability class: Buffer Overflow

EPSS: 0.009 (56.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-42536?
CVE-2026-42536 is a high-severity vulnerability in Apache Http_server, classified under Heap-based Buffer Overflow. CVSS score: 7.5/10. Published 2026-06-08.
How severe is CVE-2026-42536?
High severity. CVSS v3 base score is 7.5 out of 10.