Discourse
CVE-2021-41263
HIGH
Severity by source
AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
Lifecycle Timeline
1DescriptionNVD
rails_multisite provides multi-db support for Rails applications. In affected versions this vulnerability impacts any Rails applications using rails_multisite alongside Rails' signed/encrypted cookies. Depending on how the application makes use of these cookies, it may be possible for an attacker to re-use cookies on different 'sites' within a multi-site Rails application. The issue has been patched in v4 of the rails_multisite gem. Note that this upgrade will invalidate all previous signed/encrypted cookies. The impact of this invalidation will vary based on the application architecture.
AnalysisAI
rails_multisite provides multi-db support for Rails applications. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity. This Exposure of Sensitive Information vulnerability could allow attackers to access sensitive data that should not be disclosed.
Technical ContextAI
This vulnerability is classified as Exposure of Sensitive Information (CWE-200), which allows attackers to access sensitive data that should not be disclosed. rails_multisite provides multi-db support for Rails applications. In affected versions this vulnerability impacts any Rails applications using rails_multisite alongside Rails' signed/encrypted cookies. Depending on how the application makes use of these cookies, it may be possible for an attacker to re-use cookies on different 'sites' within a multi-site Rails application. The issue has been patched in v4 of the rails_multisite gem. Note that this upgrade will invalidate all previous signed/encrypted cookies. The impact of this invalidation will vary based on the application architecture. Affected products include: Discourse Rails Multisite.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Minimize information in error messages, implement proper access controls, encrypt sensitive data at rest and in transit.
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Same weakness CWE-200 – Information Exposure
View allSame technique Information Disclosure
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External POC / Exploit Code
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