CVE-2025-34157: Coolify Stored Cross-Site Scripting (XSS) in Project Name Field

Severity: critical (CVSS 9.0 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-08-27 · updated 2026-07-14
Weakness: CWE-20

Description

Coolify versions prior to v4.0.0-beta.420.6 are vulnerable to a stored cross-site scripting (XSS) attack in the project creation workflow. An authenticated user with low privileges can create a project with a maliciously crafted name containing embedded JavaScript. When an administrator attempts to delete the project or its associated resource, the payload executes in the admin’s browser context. This results in full compromise of the Coolify instance, including theft of API tokens, session cookies, and access to WebSocket-based terminal sessions on managed servers.

Affected products

coollabsio coolify: before 4.0.0; 4.0.0-beta100, 4.0.0-beta101, 4.0.0-beta102, 4.0.0-beta103, 4.0.0-beta104, 4.0.0-beta105 (+401) — fixed in 4.0.0

How to fix

Upgrade to a fixed version: coollabsio coolify 4.0.0. Check the vendor advisory for mitigations.

References

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