How severe is CVE-2024-21641?

CVE-2024-21641 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2024-21641 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-21641?

CVE-2024-21641 affects Flarum. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-21641?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2024-21641 have an EU (EUVD) identifier?

Yes. CVE-2024-21641 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0279.

When was CVE-2024-21641 published?

CVE-2024-21641 was published on 2024-01-05 and last updated on 2026-06-17.

CVE-2024-21641

CVE-2024-21641 is a medium-severity vulnerability in Flarum with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-601.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 1% (61st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-0279
Weakness: CWE-601
Affected product: Flarum
Published: 2024-01-05
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2024-21641?: 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.
How severe is CVE-2024-21641?: CVE-2024-21641 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2024-21641 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-21641?: CVE-2024-21641 affects Flarum. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-21641?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-21641 have an EU (EUVD) identifier?: Yes. CVE-2024-21641 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0279.
When was CVE-2024-21641 published?: CVE-2024-21641 was published on 2024-01-05 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:flarum:flarum:*:*:*:*:*:*:*:*

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