Vulnerability · Published Oct 13, 2026 · Assigned by GitHub_M
CVE-2026-55562Cronicle: Stored XSS in admin Activity Log via account full_name field
Critical 9.0
In plain English
A critical-severity cross-site scripting in Cronicle from jhuckaby. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 40% of all known vulnerabilities).
Official description
Cronicle is a multi-server task scheduler and runner, with a web based front-end UI. Prior to 0.9.119, the administrator Activity Log in htdocs/js/pages/admin/Activity.js concatenates the attacker-controlled item.user.full_name value into HTML without applying encode_entities and inserts the result through this.div.html. The bundled pixl-server-user input filter can be bypassed by a tag containing a line break because its regular expression does not match newlines. An authenticated non-administrator can update the attacker's own name through /api/user/update using a valid session and current password; when free_accounts is enabled, an anonymous attacker can instead plant the name during self-registration. The stored name executes script in an administrator's session when the Activity Log is opened, enabling administrator takeover and subsequent command execution through privileged Cronicle features. This issue is fixed in version 0.9.119.
Affected products (as reported)
Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H