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CVE-2026-123521

6.0 mediumEPSS 0.2%

Medium (6.0) in go-vikunja vikunja. EPSS 0.2% estimated probability of exploitation activity in the next 30 days.

On this page
Vikunja before 2.7.1 contains an improper restriction of excessive authentication attempts vulnerability that allows session holders to brute-force account passwords via unthrottled re-authentication endpoints. Attackers with a stolen session can guess the password via /user/settings/totp/disable without lockout, then disable TOTP without a code for persistent account takeover.

Severity

CVSS 4.0

6.0 medium
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N

CVSS 3.1

5.9 medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:N
EPSS
0.2% estimated probability of exploitation activity in the next 30 days; 15th percentile. Scored 2026-11-10. A forecast for this CVE across the internet, not for your own systems.
CWE
CWE-307 Improper Restriction of Excessive Authentication Attempts
OWASP Top 10
A07:2025 Authentication Failures
Published
Modified
NVD analysis
Deferred: the NVD does not plan to analyze it
Record from
the NVD, synced

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Affected

Versions

From the CNA's record in the CVE List.

ProductAffected
go-vikunja vikunjabefore 2.7.1

Attack patterns (CAPEC)

  • CAPEC-16 Dictionary-based Password Attack Likelihood: Medium · Severity: High
  • CAPEC-49 Password Brute Forcing Likelihood: Medium · Severity: High
  • CAPEC-560 Use of Known Domain Credentials Likelihood: High · Severity: High
  • CAPEC-565 Password Spraying Likelihood: High · Severity: High
  • CAPEC-600 Credential Stuffing Likelihood: High · Severity: High
  • CAPEC-652 Use of Known Kerberos Credentials Likelihood: Medium · Severity: High
  • CAPEC-653 Use of Known Operating System Credentials Likelihood: High · Severity: High

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.

References

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