CVE-2023-43656: matrix-org matrix-hookshot Injection

Vulnerability summary

CVE-2023-43656 is a critical (CVSS 9.0) Injection vulnerability in matrix-org matrix-hookshot. EPSS estimates a 0.32% chance of exploitation in the next 30 days, higher than 23.2% of scored vulnerabilities.

Timeline

1. 27-09-2023
   PublishedVulnerability first disclosed.
2. 20-09-2024
   Last modifiedVulnerability information updated.

Description

matrix-hookshot is a Matrix bot for connecting to external services like GitHub, GitLab, JIRA, and more. Instances that have enabled transformation functions (those that have `generic.allowJsTransformationFunctions` in their config), may be vulnerable to an attack where it is possible to break out of the `vm2` sandbox and as a result Hookshot will be vulnerable to this. This problem is only likely to affect users who have allowed untrusted users to apply their own transformation functions. If you have only enabled a limited set of trusted users, this threat is reduced (though not eliminated). Version 4.5.0 and above of hookshot include a new sandbox library which should better protect users. Users are advised to upgrade. Users unable to upgrade should disable `generic.allowJsTransformationFunctions` in the config.

• CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.