Detections
Analytics

nginx 1.30.x < 1.30.6 / 1.31.2 < 1.31.7 Heap Buffer Overflow

critical Nessus Plugin ID 371394

Synopsis

The remote web server is affected by a vulnerability.

Description

According to its Server response header, the installed version of nginx is 1.30.0 prior to 1.30.6, or 1.31.2 prior to 1.31.7. It is, therefore, affected by the following issue:

 - A vulnerability exists in NGINX Plus and NGINX Open Source when a map directive uses regex matching and the root directive or access log format references the map's regex capture variables before referencing the map output variable. Alternatively, the same result could be achieved by using a non-cacheable variable in a string expression under certain conditions. 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. 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. (CVE-2026-93479)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Upgrade to nginx 1.30.6, 1.31.7 or later.

See Also

https://my.f5.com/manage/s/article/K000162607

https://www.cve.org/CVERecord?id=CVE-2026-93479

Plugin Details

Severity: Critical

ID: 371394

File Name: nginx-CVE-2026-93479.nasl

Version: 1.1

Type: Combined

Agent: unix

Family: Web Servers

Published: 10/23/2026

Updated: 10/23/2026

Configuration: Enable paranoid mode

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: High

Score: 7.9

Percentile: 99.34

CVSS v2

Risk Factor: High

Base Score: 7.6

Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2026-93479

CVSS v3

Risk Factor: High

Base Score: 8.1

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS v4

Risk Factor: Critical

Base Score: 9.2

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

Vulnerability Information

CPE: cpe:/a:nginx:nginx

Required KB Items: Settings/ParanoidReport, installed_sw/nginx

Patch Publication Date: 10/14/2026

Vulnerability Publication Date: 10/14/2026

Reference Information

CVE: CVE-2026-93479

IAVA: 2026-A-1142