CVE-2026-15176

NGINX ngx_http_core_module vulnerability

CRITICAL 9.2

At a glance

Source
NVD
EPSS
EPSS 0.84 % · percentile 58 ()
State
PUBLISHED
Published
Updated
Assigner
f5
NVD status
Awaiting Analysis

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.

Weaknesses (CWE)

  • CWE-122 — Heap-based Buffer Overflow

References

Scores

VersionScoreVectorScored by
CVSS 3.1HIGH 8.1CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hf5
CVSS 4.0CRITICAL 9.2CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:Nf5
CVSS 4.0CRITICAL 9.2CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XNVD · f5sirt@f5.com (Secondary)
CVSS 3.1HIGH 8.1CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:HNVD · f5sirt@f5.com (Secondary)

European references

CERT-FR advisories

Affected products

ProductVersions
F5 · NGINX Plusaffected 37.1.0 < 37.1.0.1 ; affected 37.0.0 < 37.0.5.1 ; affected R36 < * ; affected R35 < * ; affected R34 < * ; affected R33 < *
F5 · NGINX Open Sourceaffected 1.31.0 < 1.31.7 ; affected 0.1.29 < 1.30.6

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD