VULNERABILITY INTELLIGENCE

CVE-2021-29453

CVSS score5.7 MEDIUM
EPSS probability1.00%
CISA KEVNot currently listed
Published2021-04-19
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H

Description

matrix-media-repo is an open-source multi-domain media repository for Matrix. Versions 1.2.6 and earlier of matrix-media-repo do not properly handle malicious images which are crafted to be small in file size, but large in complexity. A malicious user could upload a relatively small image in terms of file size, using particular image formats, which expands to have extremely large dimensions during the process of thumbnailing. The server can be exhausted of memory in the process of trying to load the whole image into memory for thumbnailing, leading to denial of service. Version 1.2.7 has a fix for the vulnerability.

Weakness classification

  • CWE-400: Uncontrolled Resource Consumption
  • CWE-770: Allocation of Resources Without Limits or Throttling

Primary references