NGINX ngx_http_rewrite_module vulnerability_CVE-2026-42945

8.1 / 10

HIGH

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

Description

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_rewrite_module module. This vulnerability exists when the rewrite directive is followed by a rewrite, if, or set directive and an unnamed Perl-Compatible Regular Expression (PCRE) capture (for example, $1, $2) with a replacement string that includes a question mark (?). An unauthenticated attacker along with conditions beyond its 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, for systems with Address Space Layout Randomization (ASLR ) disabled, code execution is possible. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Basic Information

ID CVE-2026-42945

Source f5

Published May 13, 2026 at 14:12

Affected Product

Vendor F5

Product NGINX Plus

Version R37

Affected Versions F5 NGINX Plus R36
F5 NGINX Plus R32
F5 NGINX Open Source 0.6.27

CWE Classification

CWE-122

References

my.f5.com /manage/s/article/K000161019

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