CVE-2023-36459

Mastodon vulnerable to Cross-site Scripting through oEmbed preview cards

State
Published
Severity
9.3 Critical
Published
Jul 6, 2023
Updated
Feb 13, 2025
Reserved
Jun 21, 2023

Read the record on cve.org

Description

Mastodon is a free, open-source social network server based on ActivityPub. Starting in version 1.3 and prior to versions 3.5.9, 4.0.5, and 4.1.3, an attacker using carefully crafted oEmbed data can bypass the HTML sanitization performed by Mastodon and include arbitrary HTML in oEmbed preview cards. This introduces a vector for cross-site scripting (XSS) payloads that can be rendered in the user's browser when a preview card for a malicious link is clicked through. Versions 3.5.9, 4.0.5, and 4.1.3 contain a patch for this issue.

Scores

CVSSScoreVectorSource
3.19.3 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:NGitHub_M

Weaknesses

  • CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Affected Products

ProductVersions
mastodonmastodon
  • >= 1.3, < 3.5.9Affected
  • >= 4.0.0, < 4.0.5Affected
  • >= 4.1.0, < 4.1.3Affected

References

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