Vulnerability-Lookup

GHSA-M73P-XG7Q-M8F2

Vulnerability from github – Published: 2026-07-15 15:33 – Updated: 2026-07-15 21:31

Details

Impact: This vulnerability may allow remote attackers to have limited control to modify memory contents or restart the NGINX worker process. There is no control plane exposure; this is a data plane issue only.

Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Severity

6.5 (Medium)


                  
                    CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H

8.3 (High)


                  
                    CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N

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{
  "affected": [],
  "aliases": [
    "CVE-2026-56434"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-15T15:16:45Z",
    "severity": "HIGH"
  },
  "details": "NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_ssi_module\u00a0module. This vulnerability may exist when the Server-Side Includes (SSI), proxy_pass, and proxy_buffering off\u00a0directives are configured. With this configuration, an unauthenticated attacker with man-in-the-middle (MITM) ability to control responses from an upstream server may be able to cause a heap buffer over-read in the NGINX worker process. This issue may lead to limited modification of memory or a restart of the NGINX worker process.\n\nImpact:\nThis vulnerability may allow remote attackers to have limited control to modify memory contents or restart the NGINX worker process. There is no control plane exposure; this is a data plane issue only.\n\nNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated.",
  "id": "GHSA-m73p-xg7q-m8f2",
  "modified": "2026-07-15T21:31:21Z",
  "published": "2026-07-15T15:33:07Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56434"
    },
    {
      "type": "WEB",
      "url": "https://my.f5.com/manage/s/article/K000162098"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/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-2026-56434 (GCVE-0-2026-56434)

Vulnerability from cvelistv5 – Published: 2026-07-15 14:33 – Updated: 2026-07-15 18:10

Title

NGINX ngx_http_ssi_module vulnerability

Summary

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_ssi_module module. This vulnerability may exist when the Server-Side Includes (SSI), proxy_pass, and proxy_buffering off directives are configured. With this configuration, an unauthenticated attacker with man-in-the-middle (MITM) ability to control responses from an upstream server may be able to cause a use-after-free in the NGINX worker process. This issue may lead to limited modification of memory or a restart of the NGINX worker process. Impact: This vulnerability may allow remote attackers to have limited control to modify memory contents or restart the NGINX worker process. There is no control plane exposure; this is a data plane issue only. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Severity

6.5 (Medium)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H

8.3 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-07-15 15:38 UTC

CWE

CWE-416 - Use After Free

Assigner

f5 mitre root

References

1 reference

URL	Tags
https://my.f5.com/manage/s/article/K000162098	vendor-advisorypatch

Impacted products

2 products

Vendor	Product	Version
F5	NGINX Plus	Affected: 37.0.0.1 , < 37.0.3.1 (custom) Affected: R36 , < R36 P7 (custom) Affected: R33 , < * (custom)
F5	NGINX Open Source	Affected: 1.31.2 , < 1.31.3 (custom) Affected: 0.8.11 , < 1.30.4 (custom)

Date Public

2026-07-15 14:00

Credits

F5 acknowledges p4p3r(@P4P3R-HAK)" of "싸이버원(CYBERONE) 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

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.