CVE-2026-27654
Buffer Overflow in NGINX ngx_http_dav_module Causes Process Crash
Publication date: 2026-03-24
Last updated on: 2026-03-26
Assigner: F5 Networks
Description
Description
CVSS Scores
EPSS Scores
| Probability: | |
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| f5 | nginx_plus | r32 |
| f5 | nginx_plus | r32 |
| f5 | nginx_plus | r33 |
| f5 | nginx_plus | r33 |
| f5 | nginx_plus | r34 |
| f5 | nginx_plus | r32 |
| f5 | nginx_plus | r33 |
| f5 | nginx_plus | r34 |
| f5 | nginx_plus | r36 |
| f5 | nginx_plus | r33 |
| f5 | nginx_plus | r34 |
| f5 | nginx_plus | r35 |
| f5 | nginx_plus | r36 |
| f5 | nginx_plus | r36 |
| f5 | nginx_plus | r32 |
| f5 | nginx_plus | r35 |
| f5 | nginx_open_source | From 0.5.13 (inc) to 0.9.7 (inc) |
| f5 | nginx_open_source | From 1.29.0 (inc) to 1.29.7 (exc) |
| f5 | nginx_open_source | From 1.0.0 (inc) to 1.28.3 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-122 | A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). |
Attack-Flow Graph
AI Powered Q&A
What immediate steps should I take to mitigate this vulnerability?
I don't know
Can you explain this vulnerability to me?
This vulnerability exists in the ngx_http_dav_module module of NGINX Open Source and NGINX Plus. It allows an attacker to trigger a buffer overflow in the NGINX worker process. This can cause the worker process to terminate unexpectedly or allow modification of source or destination file names outside the document root.
The vulnerability occurs when the configuration file uses the DAV module's MOVE or COPY methods, prefix location (nonregular expression location configuration), and alias directives.
The impact on integrity is limited because the NGINX worker process runs with low privileges and does not have access to the entire system.
How can this vulnerability impact me? :
This vulnerability can lead to the termination of the NGINX worker process, which may cause service disruption or downtime.
Additionally, it may allow an attacker to modify file names outside the document root, potentially leading to unauthorized changes to files managed by the server.
However, the overall impact on system integrity is constrained due to the low privileges of the NGINX worker process.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know