CVE-2026-30913
flarum/nickname: Display name injection in notification emails (autolink & markdown)
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
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.
Public exploit
A reference of the record is tagged as an exploit or proof of concept: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: a proof of concept is public.
- https://github.com/flarum/framework/security/advisories/GHSA-3c4m-j3g4-hh25 (opens in a new tab)x_refsource_CONFIRMexploit
Timeline
ID reserved
By GitHub_M
- 2 days later
· 2 days later
Published
- 1 day later
· 1 day later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium4.6 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N |
| NVDNVD · Deferred | 3.1 | Medium4.6 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.20% · top 91% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.6.
Weakness
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Packagistflarum/nicknamesGHSA-3c4m-j3g4-hh25 (opens in a new tab)
References (3)
- https://github.com/flarum/framework/security/advisories/GHSA-3c4m-j3g4-hh25 (opens in a new tab)x_refsource_CONFIRMexploit
- https://github.com/flarum/nicknames/commit/4dde99729abdce8f6e2a7437c86e38735fdcca28 (opens in a new tab)x_refsource_MISC
- https://github.com/flarum/nicknames/releases/tag/v1.8. (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-3c4m-j3g4-hh25 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-30913)Record last updated .