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FKIE_CVE-2026-53503

Vulnerability from fkie_nvd - Published: 2026-07-31 19:17 - Updated: 2026-09-08 20:51
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
Thumbor is an open-source photo thumbnail service by globo.com. Prior to 7.8.0, Thumbor's filters:convolution(<matrix>, <columns>, <should_normalize>) filter passes the user-controlled <columns> value to a C extension (thumbor/ext/filters/_convolution.c) where it is used as a divisor (for % and /) without validating columns > 0. When columns=0, the C code triggers undefined behavior; on x86_64 this reliably results in a fatal divide-by-zero trap (SIGFPE) and crashes the Thumbor process, causing a remote denial of service. This issue is fixed in 7.8.0.
References
security-advisories@github.comhttps://github.com/thumbor/thumbor/commit/447e192e3fb92e64c12e5354a56a4a7133f69d73
security-advisories@github.comhttps://github.com/thumbor/thumbor/releases/tag/7.8.0
security-advisories@github.comhttps://github.com/thumbor/thumbor/security/advisories/GHSA-cqjp-jf4r-h5q9
134c704f-9b21-4f2e-91b3-4a467353bcc0https://github.com/thumbor/thumbor/security/advisories/GHSA-cqjp-jf4r-h5q9
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "thumbor",
          "vendor": "thumbor",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 7.8.0"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Thumbor is an open-source photo thumbnail service by globo.com. Prior to 7.8.0, Thumbor\u0027s filters:convolution(\u003cmatrix\u003e, \u003ccolumns\u003e, \u003cshould_normalize\u003e) filter passes the user-controlled \u003ccolumns\u003e value to a C extension (thumbor/ext/filters/_convolution.c) where it is used as a divisor (for % and /) without validating columns \u003e 0. When columns=0, the C code triggers undefined behavior; on x86_64 this reliably results in a fatal divide-by-zero trap (SIGFPE) and crashes the Thumbor process, causing a remote denial of service. This issue is fixed in 7.8.0."
    }
  ],
  "id": "CVE-2026-53503",
  "lastModified": "2026-09-08T20:51:43.490",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-53503",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-07-31T20:14:06.472673Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-07-31T19:17:09.737",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/thumbor/thumbor/commit/447e192e3fb92e64c12e5354a56a4a7133f69d73"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/thumbor/thumbor/releases/tag/7.8.0"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/thumbor/thumbor/security/advisories/GHSA-cqjp-jf4r-h5q9"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "url": "https://github.com/thumbor/thumbor/security/advisories/GHSA-cqjp-jf4r-h5q9"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-20"
        },
        {
          "lang": "en",
          "value": "CWE-369"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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