CVE-2024-21641

Medium (4.7)—Exploit
Routine follow-upSeverity Medium 4.7. A public proof of concept exists, but no active exploitation is known.
Severity4.7Medium · CVSS 3.1
Exploitation probability1.07 %higher than 65% of CVEs · score from Nov 5, 2026
Active exploitationNonot in the CISA catalog · checked Nov 5, 06:00 PM
Public exploitAvailableNuclei template (automated mass detection)

Flarum is open source discussion platform software. Prior to version 1.8.5, the Flarum `/logout` route includes a redirect parameter that allows any third party to redirect users from a (trusted) domain of the Flarum installation to redirect to any link. For logged-in users, the logout must be confirmed. Guests are immediately redirected. This could be used by spammers to redirect to a web address using a trusted domain of a running Flarum installation. The vulnerability has been fixed and published as flarum/core v1.8.5. As a workaround, some extensions modifying the logout route can remedy this issue if their implementation is safe.

Timeline

Built from our own data: NVD, CISA KEV, FIRST EPSS, public exploits, specialised media and Orbitaley coverage.

  1. CVE record published in NVD
  2. Record last modified in NVD
  3. First public exploit

Public exploits

Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.

Affected technologies (1)

NVD record

NVD status
Modified
Published
Jan 5, 2024
Last modified
Jun 17, 2026
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N
Weakness (CWE)
CWE-601

References

Raw JSON (NVD)

Show
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      "lang": "en",
      "value": "Flarum is open source discussion platform software. Prior to version 1.8.5, the Flarum `/logout` route includes a redirect parameter that allows any third party to redirect users from a (trusted) domain of the Flarum installation to redirect to any link. For logged-in users, the logout must be confirmed. Guests are immediately redirected. This could be used by spammers to redirect to a web address using a trusted domain of a running Flarum installation. The vulnerability has been fixed and published as flarum/core v1.8.5. As a workaround, some extensions modifying the logout route can remedy this issue if their implementation is safe."
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