Cyber Resilience

CVE-2025-34157

Critical

Published: 27 August 2025

Published
27 August 2025
Modified
19 September 2025
KEV Added
Patch
CVSS Score v4 9.4 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0008 23.4th percentile
Risk Priority 19 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-34157 is a critical-severity Improper Input Validation (CWE-20) vulnerability in Coollabs Coolify. Its CVSS base score is 9.4 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 23.4th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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…

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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.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1059.007 JavaScript Execution
Adversaries may abuse various implementations of JavaScript for execution.
T1539 Steal Web Session Cookie Credential Access
An adversary may steal web application or service session cookies and use them to gain access to web applications or Internet services as an authenticated user without needing credentials.
T1555.003 Credentials from Web Browsers Credential Access
Adversaries may acquire credentials from web browsers by reading files specific to the target browser.
Why these techniques?

Stored XSS enables low-privileged authenticated attackers to execute arbitrary JavaScript (T1059.007, T1203) in an administrator's browser context during project deletion, facilitating privilege escalation (T1068) and theft of session cookies (T1539) and browser credentials including API tokens (T1555.003).

Affected Assets

coollabs
coolify
4.0.0 · ≤ 4.0.0

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-20 CWE-79

Directly implements checks on information inputs to reject invalid data before processing.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-20

Security testing and developer training directly verify and enforce proper input validation, reducing exploitability of injection and malformed-data weaknesses.

addresses: CWE-20

Security testing and evaluation at multiple SDLC stages directly detects missing or flawed input validation, with the required remediation process ensuring fixes are applied.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

addresses: CWE-20

Spam protection mechanisms perform filtering and detection on inbound/outbound messages, directly compensating for missing or weak input validation of unsolicited content.

References