Vulnerability 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.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://my.f5.com/manage/s/article/K000161019
- https://depthfirst.com/nginx-rift
- https://github.com/DepthFirstDisclosures/Nginx-Rift
FAQ
What is CVE-2026-42945?
CVE-2026-42945 is a vulnerability with a CVSS score of 8.1 (HIGH). 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 ...
How severe is CVE-2026-42945?
CVE-2026-42945 has been rated HIGH with a CVSS base score of 8.1/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-42945?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.