CVE-2026-55240: critical vulnerability in msgbyte tianji
Tianji: Remote Code Execution via lodash template evaluate pattern in survey feed templates
Published
28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.1epss 0.6%
exploitation probability
0.6%top 54% of all CVEs
observed exploitation
nono source reports it
Tianji is an open source analytics, uptime monitoring, and server status platform. Prior to 1.31.29, formatString() in src/server/utils/template.ts passes survey feedTemplate and monitor notification templates to lodash template(), while the default evaluate pattern remains enabled. A workspace administrator can store an evaluate block using the <% code %> form, and the public survey.submit endpoint renders a survey template when an unauthenticated user submits a response. The compiled template executes server-side JavaScript in the Tianji Node.js process, allowing command execution, secret disclosure, data modification, or service disruption. This issue is fixed in version 1.31.29.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Affected products
msgbyte · tianjiRelated CVEs — msgbyte tianji
In the same product, most dangerous first.