LF Edge eKuiper allows Stored XSS in Rules Functionality
Date: 2025-03
Affected: go/github.com/lf-edge/ekuiper, go/github.com/lf-edge/ekuiper/v2
Attack vector: xss
Category: vulnerability-disclosure
Severity: Medium
CVE: CVE-2024-52812
CWE: CWE-79
CVSS: 5.4 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N)

### Summary Stored Cross-Site Scripting (XSS) vulnerability allows attackers to inject malicious scripts into web applications, which can then be executed in the context of other users' browsers. This can lead to unauthorized access to sensitive information, session hijacking, and spreading of malware, impacting user data privacy and application integrity. ### Details A user with rights to modificate the service (e.g. kuiperUser role) can inject XSS Payload into Rule `id` parameter. Then, after any user with access to this service (e.g. admin) will try make any modifications with the rule (update, run, stop, delete), a payload will act in victim's browser. The issue appears as the notification to user is made in an insafe way: https://github.com/lf-edge/ekuiper/blob/dbce32d5a195cf1de949b3a6a4e29f0df0f3330d/internal/server/rest.go#L681 https://github.com/lf-edge/ekuiper/blob/dbce32d5a195cf1de949b3a6a4e29f0df0f3330d/internal/server/rest.go#L716 https://github.com/lf-edge/ekuiper/blob/dbce32d5a195cf1de949b3a6a4e29f0df0f3330d/internal/server/rest.go#L735 https://github.com/lf-edge/ekuiper/blob/dbce32d5a195cf1de949b3a6a4e29f0df0f3330d/internal/server/rest.go#L794 https://github.com/lf-edge/ekuiper/blob/dbce32d5a195cf1de949b3a6a4e29f0df0f3330d/internal/server/rest.go#L809 https://github.com/lf-edge/ekuiper/blob/dbce32d5a195cf1de949b3a6a4e29f0df0f3330d/internal/server/rest.go#L824 Such writing to 'http.ResponseWriter' bypasses HTML escaping that prevents cross-site script


Mitigations:

Architectural layers (MAESTRO):