CVE-2026-15176

Publication date 15 October 2026

Last updated 26 October 2026


Ubuntu priority

Cvss 3 Severity Score

8.1 · High

Score breakdown

Description

A vulnerability exists in NGINX Plus and NGINX Open Source when a location is configured that uses the alias directive together with rewrite and a set or return directive referencing the $request_filename variable. Alternatively, the same result could be achieved when the $request_filename variable is used in an access log format directive. An unauthenticated attacker along with conditions beyond their control can exploit this vulnerability by sending crafted HTTP requests. This may cause a heap buffer overflow in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR. Impact: This vulnerability may allow remote attackers to cause a denial-of-service (DoS) on the NGINX system or to possibly trigger a code execution. There is no control plane exposure; this is a data plane issue only. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Status

Package Ubuntu Release Status
nginx 26.10 stonking
Fixed in 1.30.4-7ubuntu1.1
26.04 LTS resolute
Fixed in 1.28.3-2ubuntu1.12
24.04 LTS noble
Fixed in 1.24.0-2ubuntu7.19
22.04 LTS jammy
Fixed in 1.18.0-6ubuntu14.22
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation
14.04 LTS trusty
Needs evaluation

Patch details

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Package Patch details
nginx

Severity score breakdown

CVSS version:

Base score 9.2 · Critical

Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Base score 8.1 · High

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

References

Related Ubuntu Security Notices (USN)

    • USN-8955-1
    • nginx vulnerabilities
    • 26 October 2026

Other references


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