Vulnerability-Lookup

GHSA-X88Q-X2R7-VG3G

Vulnerability from github – Published: 2026-05-13 18:30 – Updated: 2026-05-13 18:30

Details

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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-40701"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-13T16:16:43Z",
    "severity": "MODERATE"
  },
  "details": "NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_ssl_module\u00a0module when the ssl_verify_client\u00a0directive is set to \"on\" or \"optional,\" and the ssl_ocsp\u00a0directive is set to \"on\" or the leaf\u00a0parameters 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.\n\n\n\n\u00a0Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.",
  "id": "GHSA-x88q-x2r7-vg3g",
  "modified": "2026-05-13T18:30:55Z",
  "published": "2026-05-13T18:30:55Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40701"
    },
    {
      "type": "WEB",
      "url": "https://my.f5.com/manage/s/article/K000161021"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L",
      "type": "CVSS_V3"
    },
    {
      "score": "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

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

Vulnerability from cvelistv5 – Published: 2026-05-13 14:12 – Updated: 2026-05-13 16:07

Title

NGINX ngx_http_ssl_module vulnerability

Summary

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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-05-13 15:55 UTC

CWE

CWE-416 - Use After Free

Assigner

f5 mitre root

References

1 reference

URL	Tags
https://my.f5.com/manage/s/article/K000161021	vendor-advisorypatch

Impacted products

2 products

Vendor	Product	Version
F5	NGINX Plus	Unaffected: R37 , < * (custom) Affected: R36 , < R36 P4 (custom) Affected: R32 , < R32 P6 (custom)
F5	NGINX Open Source	Unaffected: 1.31.0 , < * (semver) Affected: 1.19.0 , < 1.30.1 (semver)

Date Public

2026-05-13 14:00

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

JSON

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Sightings

Author	Source	Type	Date	Other

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.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

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