CVE-2026-42934 MEDIUM

CVE-2026-42934: NGINX ngx_http_charset_module vulnerability

Vendor F5
Product NGINX Plus
Weakness CWE-125
Published May 13, 2026
Last update June 8, 2026

CVSS base score

4.8/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Confidentiality Low
Integrity None

CVSS vector

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

What the vulnerability does

Description

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_charset_module module. When charset, source_charset, and charset_map and proxy_pass with disabled buffering ("off") directives are configured, unauthenticated attackers can send requests that with conditions beyond the attackers' control to cause a heap buffer over-read in the NGINX worker process, leading to limited disclosure of memory or a restart.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Key dates

Disclosure timeline

May 13, 2026 CVE published
June 8, 2026 Record updated