NetSight
IP …
high8.1

CVE-2026-42945

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_rewrite_module module.

Impact

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 products

VendorProductAffected versions
F5Dos
from 4.3.0 through 4.7.0
Version 4.8.0
F5Nginx Gateway Fabric
from 1.3.0 through 1.6.2
from 2.0.0 through 2.5.1
F5Nginx Ingress Controller
from 3.5.0 through 3.7.2
from 4.0.0 through 4.0.1
from 5.0.0 through 5.4.1
F5Nginx Instance Manager
from 2.16.0 through 2.21.1
F5Nginx Open Source
from 0.6.27 through 1.30.0
F5Nginx Plus
from r32 through r36
F5Waf
from 4.9.0 through 4.16.0
from 5.1.0 through 5.8.0
from 5.9.0 through 5.12.1

Weakness classification

CWE-122CWE-131

References