CVE-2026-30913 | BDVDB-2026-319374 Detail

flarumnicknames

Description#

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.

Impact#

Per CVSS v3.1: confidentiality impact low, integrity impact low, availability impact none. Attack vector: network.

Weaknesses#

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

References#

Exploit#

No public exploit known

History#

Version 12026-03-09Record published in the CVE List.
Version 22026-03-10Most recent update recorded in the CVE List.

Published

Published: 2026-03-09
Last modified: 2026-03-10

Vendor information

Vendor: flarum
Product: nicknames

All flarum vulnerabilities

Score

4.6 Medium

EPSS

less than 1%, Very Low

Estimated chance of exploitation in the next 30 days. EPSS percentile: 9.5.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Cross-Site Scripting

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

Vulnerable
< 1.8.3
Fixed
Not stated

Scoring System

CVSS v4.0

Not available

CVSS v3.1

4.6 Medium

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N

Metric breakdown
Attack Vector	Network
Attack Complexity	Low
Privileges Required	Low
User Interaction	Required
Scope	Unchanged
Confidentiality	Low
Integrity	Low
Availability	None

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).