Flarum is open-source forum software. A session hijacking vulnerability exists in versions prior to 1.8.10 when an attacker-controlled authoritative subdomain under a parent domain (e.g., `subdomain.host.com`) sets cookies scoped to the parent domain (`.host.com`). This allows session token replacement for applications hosted on sibling subdomains (e.g., `community.host.com`) if session tokens aren't rotated post-authentication. Key Constraints are that the attacker must control any subdomain under the parent domain (e.g., `evil.host.com` or `x.y.host.com`), and the parent domain must not be on the Public Suffix List. Due to non-existent session token rotation after authenticating we can theoretically reproduce the vulnerability by using browser dev tools, but due to the browser's security measures this does not seem to be exploitable as described. Version 1.8.10 contains a patch for the issue.
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Wed, 02 Apr 2025 13:00:00 +0000
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Flarum
Flarum flarum |
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CPEs | cpe:2.3:a:flarum:flarum:*:*:*:*:*:*:*:* | |
Vendors & Products |
Flarum
Flarum flarum |
Wed, 12 Mar 2025 16:15:00 +0000
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ssvc
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Wed, 12 Mar 2025 14:15:00 +0000
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Description | Flarum is open-source forum software. A session hijacking vulnerability exists in versions prior to 1.8.10 when an attacker-controlled authoritative subdomain under a parent domain (e.g., `subdomain.host.com`) sets cookies scoped to the parent domain (`.host.com`). This allows session token replacement for applications hosted on sibling subdomains (e.g., `community.host.com`) if session tokens aren't rotated post-authentication. Key Constraints are that the attacker must control any subdomain under the parent domain (e.g., `evil.host.com` or `x.y.host.com`), and the parent domain must not be on the Public Suffix List. Due to non-existent session token rotation after authenticating we can theoretically reproduce the vulnerability by using browser dev tools, but due to the browser's security measures this does not seem to be exploitable as described. Version 1.8.10 contains a patch for the issue. | |
Title | Flarum Vulnerable to Session Hijacking via Authoritative Subdomain Cookie Overwrite | |
Weaknesses | CWE-74 | |
References |
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Metrics |
cvssV3_1
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Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2025-03-12T15:29:21.831Z
Reserved: 2025-03-06T18:06:54.462Z
Link: CVE-2025-27794

Updated: 2025-03-12T15:27:06.867Z

Status : Analyzed
Published: 2025-03-12T14:15:17.033
Modified: 2025-04-02T12:33:56.437
Link: CVE-2025-27794

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