CVE-2021-29453

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.

• CWE-400
• CWE-770

• https://github.com/turt2live/matrix-media-repo/releases/tag/v1.2.7Release Notes, Third Party Advisory
• https://github.com/turt2live/matrix-media-repo/security/advisories/GHSA-j889-h476-hh9hPatch, Third Party Advisory
• https://hub.docker.com/r/turt2live/matrix-media-repo/tags?page=1&ordering=last_updatedThird Party Advisory
• https://github.com/turt2live/matrix-media-repo/releases/tag/v1.2.7Release Notes, Third Party Advisory
• https://github.com/turt2live/matrix-media-repo/security/advisories/GHSA-j889-h476-hh9hPatch, Third Party Advisory
• https://hub.docker.com/r/turt2live/matrix-media-repo/tags?page=1&ordering=last_updatedThird Party Advisory

Published

Apr 19, 2021

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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