CVE-2026-93479 (GCVE-0-2026-93479)

Vulnerability from cvelistv5 – Published: 2026-10-14 14:40 – Updated: 2026-10-15 10:31
VLAI
Title
NGINX map directive and regex matching vulnerability
Summary
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. 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.
Severity
8.1 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
9.2 (Critical)
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
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-15 03:57 UTC
CWE
  • CWE-122 - Heap-based Buffer Overflow
Assigner
f5 CNA under the mitre root
CNA scorecard B 84/100 over 87 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
F5 NGINX Plus Affected: 37.1.0 , < 37.1.0.1 (custom)
Affected: 37.0.0 , < 37.0.5.1 (custom)
Affected: R36 , < * (custom)
Affected: R35 , < * (custom)
Affected: R34 , < * (custom)
Affected: R33 , < * (custom)
guessed Create a notification for this product.
F5 NGINX Open Source Affected: 1.31.2 , < 1.31.7 (custom)
Affected: 1.30.0 , < 1.30.6 (custom)
guessed Create a notification for this product.
Date Public
2023-01-01 00:00
Credits
F5 acknowledges "Matt Suiche" of "Tolmo, Inc." and "Mateusz Gierblinski " for bringing this issue to our attention and following the highest standards of coordinated disclosure.
Show details on NVD website
To clipboard 

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