Medium severity4.8NVD Advisory· Published May 13, 2026· Updated May 13, 2026
CVE-2026-40701
CVE-2026-40701
Description
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_ssl_module module when the ssl_verify_client directive is set to "on" or "optional," and the ssl_ocsp directive is set to "on" or the leaf parameters are configured with a resolver. With this configuration, an unauthenticated attacker can send requests along with conditions beyond its control that may cause a heap-use-after-free error in the NGINX worker process. This vulnerability may result in limited modification of data or the NGINX worker process restarting.
Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Patches
0No patches discovered yet.
Vulnerability mechanics
AI mechanics synthesis has not run for this CVE yet.
References
1News mentions
2- 18-year-old NGINX vulnerability allows DoS, potential RCEBleepingComputer · May 14, 2026
- 18-Year-Old NGINX Rewrite Module Flaw Enables Unauthenticated RCEThe Hacker News · May 14, 2026