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CVE-2026-121531

2.1 lowEPSS 0.3%

Low (2.1). EPSS 0.3% estimated probability of exploitation activity in the next 30 days.

On this page
A vulnerability has been found in Umami 3.3.x/3.4.0/3.4.1. This affects an unknown part of the file src/app/api/auth/login/route.ts of the component 2FA Policy Handler. The manipulation leads to use of single-factor authentication. It is possible to initiate the attack remotely. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

Severity

CVSS 4.0

2.1 low
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P

CVSS 3.1

6.3 medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
EPSS
0.3% estimated probability of exploitation activity in the next 30 days; 29th percentile. Scored 2026-11-04. A forecast for this CVE across the internet, not for your own systems.
CISA's assessment (SSVC)
Exploitation: PoC · Automatable: no · Technical impact: partial, assessed 2026-11-03. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
CWEs
CWE-287 Improper Authentication
CWE-308 Use of Single-factor Authentication
OWASP Top 10
A07:2025 Authentication Failures
Published
Modified
Record from
the NVD, synced

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Attack patterns (CAPEC)

  • CAPEC-22 Exploiting Trust in Client Likelihood: High · Severity: High
  • CAPEC-57 Utilizing REST's Trust in the System Resource to Obtain Sensitive Data Likelihood: Medium · Severity: Very High
  • CAPEC-94 Adversary in the Middle (AiTM) Likelihood: High · Severity: Very High
  • CAPEC-114 Authentication Abuse Severity: Medium
  • CAPEC-115 Authentication Bypass Severity: Medium
  • CAPEC-151 Identity Spoofing Likelihood: Medium · Severity: Medium
  • CAPEC-194 Fake the Source of Data Severity: Medium
  • CAPEC-593 Session Hijacking Likelihood: High · Severity: Very High
  • CAPEC-633 Token Impersonation Severity: Medium
  • CAPEC-650 Upload a Web Shell to a Web Server Severity: High

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits. More on the page of CWE-308 (14).

References

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