CVE-2020-15139

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.

CVSS v3 6.1 MEDIUM
CVSS v2.0 4.3 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

4.3^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:M/Au:N/C:N/I:P/A:N

Exploitability : 8.6 / Impact : 2.9

Access Vector NETWORK

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact NONE

Integrity Impact PARTIAL

Availability Impact NONE

References

Link	Resource
https://github.com/mybb/mybb/commit/37ad29dcd25489a37bdd89ebac761f22492558b0	Patch Third Party Advisory
https://github.com/mybb/mybb/security/advisories/GHSA-37h7-vfv6-f8rj	Patch Third Party Advisory
https://mybb.com/versions/1.8.24/	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:mybb:mybb:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2020-08-10 22:15

Updated : 2023-12-10 13:27

NVD link : CVE-2020-15139

Mitre link : CVE-2020-15139

CVE.ORG link : CVE-2020-15139

JSON object : View

Products Affected

mybb

mybb

CWE

CWE-79

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

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