TOTP bypass via unchecked CalDAV Basic authentication
Published Mar 24, 2026 · Updated Mar 24, 2026
Authentication bypass in Vikunja before 2.2.0 allows remote attackers with valid passwords to read project data through CalDAV. The CalDAV BasicAuth handler validated the username and password and returned success without checking whether the account required TOTP. Exploitation requires a valid local account password and enabled TOTP, and successful PROPFIND requests disclose project names, descriptions, and task data.
Summary
What happened
Authentication bypass in Vikunja before 2.2.0 allows remote attackers with valid passwords to read project data through CalDAV. The CalDAV BasicAuth handler validated the username and password and returned success without checking whether the account required TOTP. Exploitation requires a valid local account password and enabled TOTP, and successful PROPFIND requests disclose project names, descriptions, and task data.
The record
- CVE
- CVE-2026-33315
- Published
- Mar 24, 2026
- Updated
- Mar 24, 2026
- Vendor
- Vikunja
- Product
- Vikunja
- Classifications
- CWE-288, T1078
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 24, 2026CVE publishedPublication date reported by the CVE source.
- Mar 24, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 2.2.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- CalDAV Basic Authentication PROPFIND proof of conceptproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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