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Fencer Intel
high 7.5

CVE-2026-53504 json

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

published 3mo ago modified 2mo ago also GHSA-5vjc-7cxw-4w6j , PYSEC-2026-3616 , EUVD-2026-51610

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 49%
public exploits
0
none known

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.

Patch / fix

  • pypi thumbor 7.8.0
  • thumbor Debian 14 7.8.0-1

debian advisories DEBIAN-CVE-2026-53504

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
partial
Assessed
3mo ago

Exploit prediction

0.61% chance of exploitation in the next 30 days, higher than 49% of all scored CVEs (FIRST EPSS, 2026-11-11).

Exploits and checks

  • github.com https://github.com/thumbor/thumbor/security/advisories/GHSA-5vjc-7cxw-4w6j referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
GitHub 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
OSV 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
pypi thumbor
<7.8.0
7.8.0

Affected products

  • thumbor thumbor

Classification

Weakness
  • CWE-400 Uncontrolled Resource Consumption

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.