CVE-2020-15139

XSS in MyBB

State
Published
Severity
8.8 High
Published
Aug 10, 2020
Updated
Aug 4, 2024
Reserved
Jun 25, 2020

Read the record on cve.org

Description

In MyBB before version 1.8.24, the custom MyCode (BBCode) for the visual editor doesn't escape input properly when rendering HTML, resulting in a DOM-based XSS vulnerability. The weakness can be exploited by pointing a victim to a page where the visual editor is active (e.g. as a post or Private Message) and operates on a maliciously crafted MyCode message. This may occur on pages where message content is pre-filled using a GET/POST parameter, or on reply pages where a previously saved malicious message is quoted. After upgrading MyBB to 1.8.24, make sure to update the version attribute in the `codebuttons` template for non-default themes to serve the latest version of the patched `jscripts/bbcodes_sceditor.js` file.

Scores

CVSSScoreVectorSource
3.18.8 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HGitHub_M

Weaknesses

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

Affected Products

ProductVersions
MyBBMyBB
  • < 1.8.24Affected

References

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