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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-53501 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/thumbor/thumbor/commit/e3ae3e2500537b4d735df4144129a649374bb70b GitHub, Inc.
https://github.com/thumbor/thumbor/releases/tag/7.8.0 GitHub, Inc.
https://github.com/thumbor/thumbor/security/advisories/GHSA-mw3h-qjxj-6xg9 GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-347 Improper Verification of Cryptographic Signature GitHub, Inc.  

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-53501
NVD Published Date:
07/31/2026
NVD Last Modified:
07/31/2026
Source:
GitHub, Inc.