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CVE-2026-42946

Full vulnerability record from the local CVENow database.

Description

A vulnerability exists in the ngx_http_scgi_module and ngx_http_uwsgi_module modules that may result in excessive memory allocation or an over-read of data. When scgi_pass or uwsgi_pass is configured, an unauthenticated attacker with man-in-the-middle (MITM) ability to control responses from an upstream server may be able to read the memory of the NGINX worker process or restart it.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Severity
HIGH
CVSS score
8.3 (v4.0)
Vulnerability status
Analyzed
Source identifier
Published
2026-05-13 16:16:50.340000
Last modified
2026-10-26 14:10:00.130000
View original CVE JSON
{
  "id": "CVE-2026-42946",
  "sourceIdentifier": "[email protected]",
  "published": "2026-05-13T16:16:50.340",
  "lastModified": "2026-10-26T14:10:00.130",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A vulnerability exists in the ngx_http_scgi_module and ngx_http_uwsgi_module modules that may result in excessive memory allocation or an over-read of data. When scgi_pass or uwsgi_pass is configured, an unauthenticated attacker with man-in-the-middle (MITM) ability to control responses from an upstream server may be able to read the memory of the NGINX worker process or restart it.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated."
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad existe en los módulos ngx_http_scgi_module y ngx_http_uwsgi_module que puede resultar en asignación excesiva de memoria o una lectura excesiva de datos. Cuando scgi_pass o uwsgi_pass está configurado, un atacante no autenticado con capacidad de man-in-the-middle (MitM) para controlar las respuestas de un servidor upstream puede ser capaz de leer la memoria del proceso worker de NGINX o reiniciarlo. Nota: Las versiones de software que han alcanzado el Fin de Soporte Técnico (EoTS) no son evaluadas."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "F5",
          "product": "NGINX Plus",
          "defaultStatus": "unknown",
          "modules": [
            "ngx_http_scgi_module and ngx_http_uwsgi_module"
          ],
          "versions": [
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            },
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            }
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        },
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          "product": "NGINX Open Source",
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          "modules": [
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          ],
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          "confidentialityRequirement": "NOT_DEFINED",
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          "modifiedAttackVector": "NOT_DEFINED",
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          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "valueDensity": "NOT_DEFINED",
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    "ssvcV203": [
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          "id": "CVE-2026-42946",
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          "role": "CISA Coordinator",
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        }
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  ],
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  "references": [
    {
      "url": "https://my.f5.com/manage/s/article/K000161027",
      "source": "[email protected]",
      "tags": [
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        "Vendor Advisory"
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}