CVE-2026-27654: F5 Nginx Open Source

High severity, CVSS 8.2. EPSS: 25.1% chance of exploitation in the next 30 days.

NGINX Open Source and NGINX Plus have a vulnerability in the ngx_http_dav_module module that might allow an attacker to trigger a buffer overflow to the NGINX worker process; this vulnerability may result in termination of the NGINX worker process or modification of source or destination file names outside the document root. This issue affects NGINX Open Source and NGINX Plus when the configuration file uses DAV module MOVE or COPY methods, prefix location (nonregular expression location configuration), and alias directives. The integrity impact is constrained because the NGINX worker process user has low privileges and does not have access to the entire system. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Affected products

• F5 Nginx Open Source: from 0.5.13, up to and including 0.9.7; from 1.0.0, before 1.28.3 (fixed in 1.28.3); from 1.29.0, before 1.29.7 (fixed in 1.29.7)
• F5 Nginx Plus: version r32 only; version r33 only; version r34 only; version r35 only; version r36 only

Published 2026-03-24. Last modified 2026-07-15.