CVE-2026-42945
CRITICALAttack Surface
CVSS Vector Breakdown
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, 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 Software (13)
| Vendor | Product | Version |
|---|---|---|
| f5 | dos | 4.3.0 – 4.7.0 |
| f5 | dos | 4.8.0 |
| f5 | nginx_gateway_fabric | 1.3.0 – 1.6.2 |
| f5 | nginx_gateway_fabric | 2.0.0 – 2.5.1 |
| f5 | nginx_ingress_controller | 3.5.0 – 3.7.2 |
| f5 | nginx_ingress_controller | 4.0.0 – 4.0.1 |
| f5 | nginx_ingress_controller | 5.0.0 – 5.4.1 |
| f5 | nginx_instance_manager | 2.16.0 – 2.21.1 |
| f5 | nginx_open_source | 0.6.27 – 1.30.0 |
| f5 | nginx_plus | r32 – r36 |
| f5 | waf | 4.9.0 – 4.16.0 |
| f5 | waf | 5.1.0 – 5.8.0 |
| f5 | waf | 5.9.0 – 5.12.1 |