Exponential Backtracking Vulnerability in Thumbor by Globo.com
CVE-2026-53504

7.5HIGH

Key Information:

Vendor

Thumbor

Status
Thumbor
Vendor
CVE Published:
31 July 2026

What is CVE-2026-53504?

The vulnerability affects Thumbor, an open-source photo thumbnail service, where the convolution filter's regular expression can lead to a denial of service via exponential backtracking. By sending crafted repeated numeric input, an attacker can exhaust processing time, potentially allowing disruptions in service. This issue has been addressed and resolved in version 7.8.0.

Affected Version(s)

thumbor < 7.8.0

References

https://github.com/thumbor/thumbor/security/advisories/GH...
x_refsource_CONFIRM
https://github.com/thumbor/thumbor/commit/3f38fe1610d2016...
x_refsource_MISC
https://github.com/thumbor/thumbor/releases/tag/7.8.0
x_refsource_MISC

CVSS V3.1

Score:
7.5
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.