Authorization Bypass in Umami Record API Endpoint
CVE-2026-121582

6.9MEDIUM

Key Information:

Vendor

Umami Software

Status
Umami
Vendor
CVE Published:
3 November 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-121582?

A vulnerability exists in the Umami analytics platform affecting versions up to 3.4.1, specifically within the Record API Endpoint's function in src/app/api/record/route.ts. This security flaw allows an unauthorized entity to manipulate the 'Website' argument, resulting in an authorization bypass. The potential for remote exploitation means that attackers can launch this exploit without needing direct access to the internal network. Despite early disclosure efforts to the vendor, no response was received, raising concerns about the platform's security responsiveness.

Affected Version(s)

Umami 3.4.0

Umami 3.4.1

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-121582 - Proof of Concept

References

https://vuldb.com/vuln/430425
vdb-entrytechnical-description
https://vuldb.com/vuln/430425/cti
signaturepermissions-required
https://vuldb.com/cve/CVE-2026-121582
third-party-advisory

CVSS V4

Score:
6.9
Severity:
MEDIUM
Confidentiality:
None
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

waterhunter (VulDB User)
VulDB CNA Team
.