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CVE-2026-42536 Apache CVE debrief

CVE-2026-42536 is a Heap-based Buffer Overflow vulnerability in Apache HTTP Server with mod_xml2enc, xml2StartParse, and untrusted content. This issue affects Apache HTTP Server versions from 2.4.0 through 2.4.67. Users are recommended to upgrade to version 2.4.68, which fixes the issue.

Vendor
Apache
Product
HTTP Server
CVSS
HIGH 7.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-08
Original CVE updated
2026-06-09
Advisory published
2026-06-08
Advisory updated
2026-06-09

Who should care

Users of Apache HTTP Server versions 2.4.0 through 2.4.67 should upgrade to version 2.4.68 to fix the vulnerability.

Technical summary

The vulnerability has a CVSS score of 7.5 and a severity of HIGH. The CVSS vector is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. The weakness is classified as CWE-122.

Defensive priority

HIGH

Recommended defensive actions

  • Upgrade to Apache HTTP Server version 2.4.68 or later.

Evidence notes

The vulnerability was published on 2026-06-08T16:16:39.263Z and modified on 2026-06-09T15:55:19.853Z. The CVE record can be found at [cve-org]. The NVD detail can be found at [nvd].

Official resources

CVE-2026-42536 was disclosed on 2026-06-08.