cbcvebase.
CVE-2026-42945
published 2026-05-13

CVE-2026-42945: 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…

critical9.2CVSS 4.0
AVNACHATNPRNUINVCHVIHVAHSCNSINSANEXCRXIRXARXMAVXMACXMATXMPRXMUIXMVCXMVIXMVAXMSCXMSIXMSAXSXAUXRXVXREXUX
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, 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.

Affected

9 ranges
VendorProductVersion rangeFixed in
f5nginx_open_source>= 0.6.27 < 1.30.11.30.1
f5nginx_plus
f5nginx_plus
f5nginx_plus>= R32 < R32 P6R32 P6
f5nginx_plus>= R36 < R36 P4R36 P4
insights-proxyinsights-proxy-container-rhel9
nginx_1.24nginx
nginx_1.26nginx
ubuntunginx

CVSS provenance

nvdv4.09.2CRITICALCVSS: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:X
vulncheck9.2CRITICAL