Description
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_rewrite_module module. This vulnerability exists when a rewrite directive uses a regex pattern with distinct, overlapping Perl-Compatible Regular Expression (PCRE) captures (for example, ^/((.*))$) and a replacement string that references multiple such captures (for example, $1$2) in a redirect or arguments context. 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. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Problem types
CWE-122 Heap-based Buffer Overflow
Product status
37.0 (custom) before 37.0.1.1
R36 (custom) before R36 P5
R32 (custom) before R32 P7
1.31.0 (custom) before 1.31.1
1.30.0 (custom) before 1.30.2
0.1.17 (custom)
Credits
"F5 acknowledges Mufeed VH of Winfunc Research, Nebula Security (@nebusecurity), and Vexera AI for bringing this issue to our attention and following the highest standards of coordinated disclosure."
References
www.openwall.com/lists/oss-security/2026/05/22/14
my.f5.com/manage/s/article/K000161377