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Fencer Intel
medium 5.4

CVE-2026-123527 json

Vikunja 2.4.0 before 2.7.1 API Token Scope Collision Authorization Bypass

published 21d ago modified 4d ago also EUVD-2026-119412 , GHSA-j5v7-qcwp-5g32

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
5.4
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 14%
public exploits
0
none known

Summary

Vikunja from 2.4.0 before 2.7.1 contains an authorization bypass vulnerability that allows token holders to perform unintended operations due to colliding v1 and v2 API token permission keys. Attackers with a token scoped to read project backgrounds can delete them via the v2 DELETE background route, and bucket create-only tokens can update existing buckets.

Patch / fix

  • go-vikunja vikunja 2.7.1

Is CVE-2026-123527 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.

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Exploit prediction

0.24% chance of exploitation in the next 30 days, higher than 14% 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:L/VA:L/SC:N/SI:N/SA:N
CNA 3.1 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
CNA 4.0 5.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/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 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L

Affected products

  • go-vikunja vikunja

Classification

Weakness

References

Sources

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.