CVE-2026-20719 (GCVE-0-2026-20719)

Vulnerability from cvelistv5 – Published: 2026-03-25 16:30 – Updated: 2026-03-26 17:11
VLAI?
Title
DoS via URL Previews Rendering Malicious SVGs
Summary
Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to prevent rendering of external SVGs on link embeds which allows unauthenticated users to crash the Mattermost webapp and desktop app via creating an issue or PR on GitHub.. Mattermost Advisory ID: MMSA-2026-00595
Severity ?
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
CWE
  • CWE-754 - Improper Check for Unusual or Exceptional Conditions
Assigner
References
Impacted products
Vendor Product Version
Mattermost Mattermost Affected: 11.4.0 , ≤ 11.4.0 (semver)
Affected: 11.3.0 , ≤ 11.3.1 (semver)
Affected: 11.2.0 , ≤ 11.2.3 (semver)
Affected: 10.11.0 , ≤ 10.11.11 (semver)
Unaffected: 11.5.0
Unaffected: 11.4.1
Unaffected: 11.3.2
Unaffected: 11.2.4
Unaffected: 10.11.12
Create a notification for this product.
Credits
mk7120
Show details on NVD website
To clipboard 

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Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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