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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2025-27794 Detail

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 3.x Severity and Vector Strings:

NIST CVSS score
NIST: NVD
Base Score:  N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
Base Score:  6.8 MEDIUM
Vector:  CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N

References to Advisories, Solutions, and Tools

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Hyperlink Resource
https://github.com/flarum/framework/commit/a05aaea3ee1e0a8b870935183193cd6052f1d402
https://github.com/flarum/framework/releases/tag/v1.8.10
https://github.com/flarum/framework/security/advisories/GHSA-hg9j-64wp-m9px

Weakness Enumeration

CWE-ID CWE Name Source
CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-27794
NVD Published Date:
03/12/2025
NVD Last Modified:
03/12/2025
Source:
GitHub, Inc.