Medium

Flarum's logout Route allows open redirects

  • Disclosed: 05.01.2024
  • Updated: 11.10.2026 10:22

Impact

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. Sample: example.com/logout?return=https://google.com. 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.

Some ecosystem extensions modifying the logout route have already been affected. Sample: https://discuss.flarum.org/d/22229-premium-wordpress-integration/526

Patches

The vulnerability has been fixed and published as flarum/core v1.8.5. All communities running Flarum should upgrade as soon as possible to v1.8.5 using:

composer update --prefer-dist --no-dev -a -W

You can then confirm you run the latest version using:

composer show flarum/core

Workarounds

Some extensions modifying the logout route can remedy this issue if their implementation is safe. In any case we recommend updating to 1.8.5.

References

For any questions or comments on this vulnerability, please visit https://discuss.flarum.org/

For support questions, create a discussion at https://discuss.flarum.org/t/support.

A reminder that if you ever become aware of a security issue in Flarum, please report it to us privately by emailing security@flarum.org, and we will address it promptly.

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
Composer package flarum/core < 1.8.5 1.8.5
Composer package flarum/framework < 1.8.5 1.8.5

References

CVSS score 6.5/10
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
Weakness (CWE)
CWE-601
Platform
Composer
Package
flarum/core, flarum/framework
Disclosed
05.01.2024
Updated
11.10.2026 10:22

Sources and licenses

OSV / GitHub Advisory Database - GHSA-733r-8xcp-w9mr - CC BY 4.0

Vulnerability history: flarum/core

All published vulnerabilities of this package (Composer package), newest first. Shows whether this is a one-off slip or a package that needs watching.

All (9) in the archive
Total entries
9
First → latest
06.2021 04.2026
Without a fix
0
Exploited in attacks
0

Severity breakdown

  • Critical 2
  • High 1
  • Medium 5
  • Low 1

Disclosures per year

  1. 2021: 1
  2. 2022: 1
  3. 2023: 4
  4. 2024: 1
  5. 2025: 1
  6. 2026: 1
Severity:
  1. Flarum's logout Route allows open redirects this entry
    Medium · 6.5 CVE-2024-21641 < 1.8.5 1.8.5
  2. High · 7.1 CVE-2023-40033 < 1.8.0 1.8.0
  3. Critical · 9.0 CVE-2022-41938 >= 1.5.0, < 1.6.2 1.6.2
  4. Critical · 10.0 CVE-2021-32671 >= 1.0.0, < 1.0.2 1.0.2

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