CVE-2026-42945

Summary

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

VendorProductVersion RangeStatus
F5NGINX PlusR37 < *unaffected
F5NGINX PlusR36 < R36 P4affected
F5NGINX PlusR32 < R32 P6affected
F5NGINX Open Source1.31.0 < *unaffected
F5NGINX Open Source0.6.27 < 1.30.1affected

Weaknesses

  • CWE-122: CWE-122 Heap-based Buffer Overflow.

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: total

CVE Program Container

Additional References

nginx: NGINX: Arbitrary Code Execution Vulnerability

Additional References

References