CVE-2026-123511 json
Vikunja before 2.7.1 Resource Exhaustion via CalDAV VTODO RELATED-TO Entries
published 21d ago modified 4d ago also EUVD-2026-119396 , GHSA-c934-xjq2-mrg3
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository go-vikunja/vikunja. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 4.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 19%
- public exploits
- 0
- none known
Summary
Vikunja before 2.7.1 contains an uncontrolled resource consumption vulnerability that allows authenticated CalDAV clients to create unbounded dummy tasks by sending VTODOs with thousands of RELATED-TO properties. Attackers can repeat unknown related UIDs in a single PUT request to generate thousands of task, relation, and event rows, bloating the database and overloading the event pipeline.
Patch / fix
- go-vikunja vikunja 2.7.1
Is CVE-2026-123511 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerExploit prediction
0.27% chance of exploitation in the next 30 days, higher than 19% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N |
| CNA | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L |
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/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 |
| NVD | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L |
Affected products
- go-vikunja vikunja
Classification
- Weakness
-
- CWE-770 Allocation of Resources Without Limits or Throttling
References
-
github.com
/go-vikunja/vikunja/security/advisories/GHSA-c934-xjq2-mrg3
vendor-advisory, advisory
-
vulncheck.com
/advisories/vikunja-before-2.7.1-resource-exhaustion-via-caldav-vtodo-related-to-entries
third-party-advisory
Sources
- CVE List CVE-2026-123511
- NVD CVE-2026-123511
- Maintainer advisory GHSA-c934-xjq2-mrg3
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of go-vikunja/vikunja published their own advisory on GitHub. Reviewed sources take precedence over it.