CVE-2026-30913

Flarum is open-source forum software. When the flarum/nicknames extension is enabled, a registered user can set their nickname to a string that email clients interpret as a hyperlink. The nickname is inserted verbatim into plain-text notification emails, and recipients may be misled into visiting attacker-controlled domains.

CVSS v3 4.6 MEDIUM

4.6^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.1 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/flarum/framework/security/advisories/GHSA-3c4m-j3g4-hh25
https://github.com/flarum/nicknames/commit/4dde99729abdce8f6e2a7437c86e38735fdcca28
https://github.com/flarum/nicknames/releases/tag/v1.8.
https://github.com/flarum/framework/security/advisories/GHSA-3c4m-j3g4-hh25

Configurations

No configuration.

History

No history.

Information

Published : 2026-03-10 17:40

Updated : 2026-06-17 10:33

NVD link : CVE-2026-30913

Mitre link : CVE-2026-30913

CVE.ORG link : CVE-2026-30913

JSON object : View

Products Affected

No product.

CWE

CWE-79

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

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