CVE-2026-53505

Thumbor proportion filter allows unbounded post-transform resize leading to remote DoS

Published Jul 31, 2026 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Description
Thumbor is an open-source photo thumbnail service by globo.com. Prior to 7.8.0, Thumbor's filters:proportion(<value>) filter does not enforce an upper bound on <value> and runs in the post-transform phase. An attacker can trigger extremely large resizes (CPU/memory exhaustion) and cause denial of service. This issue is fixed in 7.8.0.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
Github GHSA Github GHSA GHSA-phj3-59pf-cp83 Thumbor proportion filter allows unbounded post-transform resize leading to remote DoS
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Thumbor
Thumbor thumbor
Vendors & Products Thumbor
Thumbor thumbor
Type Values Removed Values Added
Description Thumbor is an open-source photo thumbnail service by globo.com. Prior to 7.8.0, Thumbor's filters:proportion(<value>) filter does not enforce an upper bound on <value> and runs in the post-transform phase. An attacker can trigger extremely large resizes (CPU/memory exhaustion) and cause denial of service. This issue is fixed in 7.8.0.
Title Thumbor proportion filter allows unbounded post-transform resize leading to remote DoS
Weaknesses CWE-400
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Aug 3, 2026, 5:20 PM
Reserved
Jun 9, 2026, 5:05 PM
Status
Deferred
Published
Jul 31, 2026, 7:17 PM
Modified
Sep 8, 2026, 8:51 PM