Vulnerability-Lookup

GHSA-5VJC-7CXW-4W6J

Vulnerability from github – Published: 2026-07-31 18:58 – Updated: 2026-07-31 18:58

Summary

Thumbor has Regex Denial of Service (ReDoS) in `convolution` filter

Details

Summary

The regular expression used to parse the convolution filter exhibits exponential-time backtracking for certain inputs, enabling a Regular Expression Denial of Service (ReDoS).

Details

The RegExp for convolution is defined as convolution\((?:\s*((?:[-]?[\d]+\.?[\d]*[;])*(?:[-]?[\d]+\.?[\d]*))\s*)(?:,\s*([\d]+)\s*)(?:,\s*([Tt]rue|[Ff]alse|1|0)\s*)?\). Within this expression a dangerous subpattern effectively behaves like (\d+)*,\d+.

PoC

A filter string containing many repeated values will exhaust re.match: - convolution(-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11) - http://localhost:8888/unsafe/0x0/smart/filters:convolution(-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11)/x.png

The evaluation occurs on https://github.com/thumbor/thumbor/blob/master/thumbor/filters/init.py#L189.

Impact

A specially crafted URL will lead to denial of service, as new images won't be processed until re.match returns.

Severity

7.5 (High)


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

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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 7.7.7"
      },
      "package": {
        "ecosystem": "PyPI",
        "name": "thumbor"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7.8.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-53504"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-07-31T18:58:28Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Summary\nThe regular expression used to parse the `convolution` filter exhibits exponential-time backtracking for certain inputs, enabling a Regular Expression Denial of Service (ReDoS).\n\n### Details\nThe RegExp for `convolution` is defined as `convolution\\((?:\\s*((?:[-]?[\\d]+\\.?[\\d]*[;])*(?:[-]?[\\d]+\\.?[\\d]*))\\s*)(?:,\\s*([\\d]+)\\s*)(?:,\\s*([Tt]rue|[Ff]alse|1|0)\\s*)?\\)`. Within this expression a dangerous subpattern effectively behaves like `(\\d+)*,\\d+`.\n\n### PoC\nA filter string containing many repeated values will exhaust `re.match`:\n- `convolution(-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11)`\n- http://localhost:8888/unsafe/0x0/smart/filters:convolution(-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11;-11)/x.png\n\nThe evaluation occurs on https://github.com/thumbor/thumbor/blob/master/thumbor/filters/__init__.py#L189.\n\n### Impact\nA specially crafted URL will lead to denial of service, as new images won\u0027t be processed until `re.match` returns.",
  "id": "GHSA-5vjc-7cxw-4w6j",
  "modified": "2026-07-31T18:58:28Z",
  "published": "2026-07-31T18:58:28Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/thumbor/thumbor/security/advisories/GHSA-5vjc-7cxw-4w6j"
    },
    {
      "type": "WEB",
      "url": "https://github.com/thumbor/thumbor/commit/3f38fe1610d20168e91f76d432212de30727eb2e"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/thumbor/thumbor"
    },
    {
      "type": "WEB",
      "url": "https://github.com/thumbor/thumbor/releases/tag/7.8.0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Thumbor has Regex Denial of Service (ReDoS) in `convolution` filter"
}

CVE-2026-53504 (GCVE-0-2026-53504)

Vulnerability from cvelistv5 – Published: 2026-07-31 18:57 – Updated: 2026-07-31 23:31

Title

Thumbor has Regex Denial of Service (ReDoS) in `convolution` filter

Summary

Thumbor is an open-source photo thumbnail service by globo.com. Prior to 7.8.0, the convolution filter regular expression performs exponential backtracking on crafted repeated numeric input, allowing a URL request to exhaust processing time. This issue is fixed in 7.8.0.

Severity

7.5 (High)


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

SSVC

Exploitation: poc Automatable: yes Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-400 - Uncontrolled Resource Consumption

Assigner

GitHub_M

References

3 references

URL	Tags
https://github.com/thumbor/thumbor/security/advis…	x_refsource_CONFIRM
https://github.com/thumbor/thumbor/commit/3f38fe1…	x_refsource_MISC
https://github.com/thumbor/thumbor/releases/tag/7.8.0	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
thumbor	thumbor	Affected: < 7.8.0

Show details on NVD website

JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-53504",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-31T23:31:09.431241Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-07-31T23:31:37.588Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/thumbor/thumbor/security/advisories/GHSA-5vjc-7cxw-4w6j"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "thumbor",
          "vendor": "thumbor",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 7.8.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Thumbor is an open-source photo thumbnail service by globo.com. Prior to 7.8.0, the convolution filter regular expression performs exponential backtracking on crafted repeated numeric input, allowing a URL request to exhaust processing time. This issue is fixed in 7.8.0."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "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"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-400",
              "description": "CWE-400: Uncontrolled Resource Consumption",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-31T18:57:19.257Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/thumbor/thumbor/security/advisories/GHSA-5vjc-7cxw-4w6j",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/thumbor/thumbor/security/advisories/GHSA-5vjc-7cxw-4w6j"
        },
        {
          "name": "https://github.com/thumbor/thumbor/commit/3f38fe1610d20168e91f76d432212de30727eb2e",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/thumbor/thumbor/commit/3f38fe1610d20168e91f76d432212de30727eb2e"
        },
        {
          "name": "https://github.com/thumbor/thumbor/releases/tag/7.8.0",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/thumbor/thumbor/releases/tag/7.8.0"
        }
      ],
      "source": {
        "advisory": "GHSA-5vjc-7cxw-4w6j",
        "discovery": "UNKNOWN"
      },
      "title": "Thumbor has Regex Denial of Service (ReDoS) in `convolution` filter"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-53504",
    "datePublished": "2026-07-31T18:57:19.257Z",
    "dateReserved": "2026-06-09T17:05:25.059Z",
    "dateUpdated": "2026-07-31T23:31:37.588Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

Action not permitted

GHSA-5VJC-7CXW-4W6J

Summary

Details

PoC

Impact

CVE-2026-53504 (GCVE-0-2026-53504)

Tags

Sightings

Nomenclature