CVE-2024-56515

mediumpriority · track · 26EPSS 0.006 · 51 %ileDEEUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.65% (51st) EPSS
CVSS 6.5 · medium
Is it mine?
3 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · osv · nvd

EPSS · scored 2026-10-27

Matrix Media Repo (MMR) is a highly configurable multi-homeserver media repository for Matrix. If SVG or JPEGXL thumbnailers are enabled (they are disabled by default), a user may upload a file which claims to be either of these types and request a thumbnail to invoke a different decoder in ImageMagick. In some ImageMagick installations, this includes the capability to run Ghostscript to decode the image/file. If MP4 thumbnailers are enabled (also disabled by default), the same issue as above may occur with the ffmpeg installation instead. MMR uses a number of other decoders for all other file types when preparing thumbnails. Theoretical issues are possible with these decoders, however in testing they were not possible to exploit. This is fixed in MMR v1.3.8. MMR now inspects the mimetype of media prior to thumbnailing, and picks a thumbnailer based on those results instead of relying on user-supplied values. This may lead to fewer thumbnails when obscure file shapes are used. This also helps narrow scope of theoretical issues with all decoders MMR uses for thumbnails. Users are advised to upgrade. Users unable to upgrade may disable the SVG, JPEGXL, and MP4 thumbnail types in the MMR config which prevents the decoders from being invoked. Further disabling uncommon file types on the server is recommended to limit risk surface. Containers and other similar technologies may also be used to limit the impact of vulnerabilities in external decoders, like ImageMagick and ffmpeg. Some installations of ImageMagick may disable "unsafe" file types, like PDFs, already. This option can be replicated to other environments as needed. ffmpeg may be compiled with limited decoders/codecs. The Docker image for MMR disables PDFs and similar formats by default.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

  • Fixedgovulncheck-vulndb-0.0.20250128T150132-150000.1.29.1.noarch as component of SUSE Linux Enterprise Module for Package Hub 15 SP6suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedgovulncheck-vulndb-0.0.20250128T150132-150000.1.29.1.noarch as component of openSUSE Leap 15.6suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

02

cvss

Technical severity, 0–10. One row per scoring source.

6.8
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 3.6
v3.16.8mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:N/A:Nsecondary · ENISA EU
v3.16.8mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:N/A:Nsecondary · security-advisories@github.comexploitability 2.3 · impact 4
v3.16.8mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:N/A:Nsecondary · OSV
v3.16mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:Usecondary · CVSS-BT (t0sche)
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-434USCWE-502USCWE-502US
05

affected products (3)

Products and version ranges known to be affected.

06

advisories (3)

Vendor and ecosystem advisories describing this.

  • SUSE-SU-2025:0297-1Security update for govulncheck-vulndb2025-01-30csaf · suse_csafDE

    Security update for govulncheck-vulndb

  • GHSA-rcxc-wjgw-579rMatrix Media Repo (MMR) allows untrusted file formats can be thumbnailed, invoking potentially further untrusted decoders2025-01-16ghsa · osvUS

    ### Impact If SVG or JPEGXL thumbnailers are enabled (they are disabled by default), a user may upload a file which claims to be either of these types and request a thumbnail to invoke a different decoder in ImageMagick. In some ImageMagick installations, this includes the capability to run Ghostscript to decode the image/file. If MP4 thumbnailers are enabled (also disabled by default), the same issue as above may occur with the ffmpeg installation instead. MMR uses a number of other decoders for all other file types when preparing thumbnails. Theoretical issues are possible with these decoders, however in testing they were not possible to exploit. ### Patches This is fixed in [MMR v1.3.8](https://github.com/t2bot/matrix-media-repo/releases/tag/v1.3.8). MMR now inspects the mimetype of media prior to thumbnailing, and picks a thumbnailer based on those results instead of relying on user-supplied values. This may lead to fewer thumbnails when obscure file shapes are used. This also helps narrow scope of theoretical issues with all decoders MMR uses for thumbnails. ### Workarounds Disabling the SVG, JPEGXL, and MP4 thumbnail types in the MMR config prevents the decoders from being invoked. Further disabling uncommon file types on the server is recommended to limit risk surface. Containers and other similar technologies may also be used to limit the impact of vulnerabilities in external decoders, like ImageMagick and ffmpeg. Some installations of ImageMagick may disable "unsafe" file types, like PDFs, already. This option can be replicated to other environments as needed. ffmpeg may be compiled with limited decoders/codecs. The Docker image for MMR disables PDFs and similar formats by default. ### References A similar issue was discovered in Synapse: https://github.com/element-hq/synapse/security/advisories/GHSA-vp6v-whfm-rv3g

  • GO-2025-3400Matrix Media Repo (MMR) allows untrusted file formats can be thumbnailed, invoking potentially further untrusted decoders in github.com/t2bot/matrix-media-repo2025-01-16vendor · osvUS

    Matrix Media Repo (MMR) allows untrusted file formats can be thumbnailed, invoking potentially further untrusted decoders in github.com/t2bot/matrix-media-repo

07

also known as (5)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdosvnvdsuse_csafNVDCVE.orgMITRE
published 2025-01-16modified 2026-06-17
09

references (7)

External citations — patches, advisories, analysis.

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