FKIE_CVE-2026-55420

Vulnerability from fkie_nvd - Published: 2026-07-09 18:16 - Updated: 2026-07-09 19:33
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, under certain non-default configurations, processing of PDF uploads could be exploited to obtain RCE on the server. This issue is patched in 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5.
References
security-advisories@github.comhttps://github.com/discourse/discourse/commit/ca5a7e06167561928556afa2f237d67e459c6914
security-advisories@github.comhttps://github.com/discourse/discourse/releases/tag/v2026.1.5
security-advisories@github.comhttps://github.com/discourse/discourse/releases/tag/v2026.4.2
security-advisories@github.comhttps://github.com/discourse/discourse/releases/tag/v2026.5.1
security-advisories@github.comhttps://github.com/discourse/discourse/releases/tag/v2026.6.0
security-advisories@github.comhttps://github.com/discourse/discourse/security/advisories/GHSA-7wq5-jgww-5rw3
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "discourse",
          "vendor": "discourse",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 2026.5.0-latest, \u003c 2026.5.1"
            },
            {
              "status": "affected",
              "version": "\u003e= 2026.4.0-latest, \u003c 2026.4.2"
            },
            {
              "status": "affected",
              "version": "\u003e= 2026.1.0-latest, \u003c 2026.1.5"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, under certain non-default configurations, processing of PDF uploads could be exploited to obtain RCE on the server. This issue is patched in 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5."
    }
  ],
  "id": "CVE-2026-55420",
  "lastModified": "2026-07-09T19:33:38.837",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.6,
        "impactScore": 5.9,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-07-09T18:16:54.440",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/discourse/discourse/commit/ca5a7e06167561928556afa2f237d67e459c6914"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/discourse/discourse/releases/tag/v2026.1.5"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/discourse/discourse/releases/tag/v2026.4.2"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/discourse/discourse/releases/tag/v2026.5.1"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/discourse/discourse/releases/tag/v2026.6.0"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/discourse/discourse/security/advisories/GHSA-7wq5-jgww-5rw3"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-78"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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