CVE-2026-27654 NGINX ngx_http_dav_module vulnerability
Attackers can trigger a buffer overflow in NGINX DAV module, causing worker termination or file name modification outside the document root.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-27654?
CVE-2026-27654 is a high-severity memory corruption vulnerability in F5 NGINX Open Source, published on 24 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Which versions are affected by CVE-2026-27654?
2 open source packages ship an affected version, including nginx and nginx-gateway. It affects 2 products.
| Package | Affected | Fixed in |
|---|---|---|
nginx Bitnami | From 0.5.13 | 1.28.3, 1.29.7 |
nginx-gateway Bitnami | From 0.5.13 | 1.28.3, 1.29.7 |
Products include F5 Nginx Open Source, F5 Nginx Plus.
How do I fix CVE-2026-27654?
Upgrade nginx to a fixed version for your release line: 1.28.3 or 1.29.7.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-27654 being exploited?
There is no known exploitation of CVE-2026-27654 in the wild and no public exploit code.
Public exploit code: 3 proofs of concept on GitHub.
Other vulnerabilities in F5 NGINX Open Source
Sources
Also known as ALPINE-CVE-2026-27654, AZL-80774, BELL-CVE-2026-27654, BIT-nginx-2026-27654, BIT-nginx-gateway-2026-27654, CLSA-2026-1776766448 and 14 more.