CVE-2026-40701 (GCVE-0-2026-40701)

Vulnerability from cvelistv5 – Published: 2026-05-13 14:12 – Updated: 2026-05-13 16:07
VLAI?
Title
NGINX ngx_http_ssl_module vulnerability
Summary
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.
Severity ?
4.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
6.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N
CWE
Assigner
f5
References
Impacted products
Vendor Product Version
F5 NGINX Plus Unaffected: R37 , < * (custom)
Affected: R36 , < R36 P4 (custom)
Affected: R32 , < R32 P6 (custom)
Create a notification for this product.
    F5 NGINX Open Source Unaffected: 1.31.0 , < * (semver)
Affected: 1.19.0 , < 1.30.1 (semver)
Create a notification for this product.
Credits
F5 acknowledges Zhenpeng (Leo) Lin of depthfirst for bringing this issue to our attention and following the highest standards of coordinated disclosure.
Show details on NVD website
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Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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