FKIE_CVE-2026-53501

Vulnerability from fkie_nvd - Published: 2026-07-31 19:17 - Updated: 2026-07-31 20:16
Severity
8.2 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L
Summary
Thumbor is an open-source photo thumbnail service by globo.com. Prior to 7.8.0, Thumbor’s HMAC validation can be bypassed due to the use of Python’s .replace() when removing the signature from the URL before validation. Since .replace() removes all occurrences of the substring, an attacker can insert the same signature multiple times in the URL and manipulate the final URL used for validation. This allows crafting URLs where the validated string differs from the actual requested resource, enabling loading images from unintended domains or paths. This issue is fixed in 7.8.0.
References
security-advisories@github.comhttps://github.com/thumbor/thumbor/commit/e3ae3e2500537b4d735df4144129a649374bb70b
security-advisories@github.comhttps://github.com/thumbor/thumbor/releases/tag/7.8.0
security-advisories@github.comhttps://github.com/thumbor/thumbor/security/advisories/GHSA-mw3h-qjxj-6xg9
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\u2019s HMAC validation can be bypassed due to the use of Python\u2019s .replace() when removing the signature from the URL before validation. Since .replace() removes all occurrences of the substring, an attacker can insert the same signature multiple times in the URL and manipulate the final URL used for validation. This allows crafting URLs where the validated string differs from the actual requested resource, enabling loading images from unintended domains or paths. This issue is fixed in 7.8.0."
    }
  ],
  "id": "CVE-2026-53501",
  "lastModified": "2026-07-31T20:16:51.280",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 8.2,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 4.2,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-53501",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-07-31T19:57:48.500225Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-07-31T19:17:09.413",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/thumbor/thumbor/commit/e3ae3e2500537b4d735df4144129a649374bb70b"
    },
    {
      "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-mw3h-qjxj-6xg9"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-347"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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