Buffer overflow in Apache Http_server
CVE-2026-34355
A buffer overflow in mod_proxy_html in Apache HTTP Server 2.4.67 and earlier allows an attack by an untrusted backend. Users are recommended to upgrade to version 2.4.68, which fixes this issue.
Vulnerability class: Buffer Overflow
EPSS: 0.009 (57.1th 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
- Apache Http_server
- Apache Software Foundation Http Server — versions 2.4.0
Weakness classification (CWE)
References
- security@apache.org (vendor-advisory, Vendor Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List)
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Frequently asked questions
- What is CVE-2026-34355?
- CVE-2026-34355 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-2026-34355?
- High severity. CVSS v3 base score is 7.5 out of 10.