High · published May 13, 2026
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.
| Product | Versions | Fixed in |
|---|---|---|
| f5/dos | ≥ 4.3.0, ≤ 4.7.0 | — |
| f5/dos | all versions | — |
| 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 | — |