CVE-2026-123526 (CVSS 5.4)

Description

Vikunja before 2.7.1 contains a mass assignment vulnerability that allows any authenticated user to set the read-only external_id field through the team create and update endpoints. Attackers can tag a team they create or administer as externally managed, permanently blocking removal of every member and causing SSO members to be dropped from the team at their next login.

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CVSS v3.1 Score

5.4

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L

EPSS — Exploit Prediction

0.0026

Probability of exploitation

0.17%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-915 CWE-915

References

Other References

https://github.com/go-vikunja/vikunja/security/advisories/GHSA-fjrf-gjmg-9v6g https://www.vulncheck.com/advisories/vikunja-before-2.7.1-mass-assignment-via-team-external-id-field https://github.com/go-vikunja/vikunja/security/advisories/GHSA-fjrf-gjmg-9v6g

Frequently Asked Questions

What is CVE-2026-123526? +

Vikunja before 2.7.1 contains a mass assignment vulnerability that allows any authenticated user to set the read-only external_id field through the team create and update endpoints. Attackers can tag a team they create or administer as externally managed, permanently blocking removal of every member and causing SSO members to be dropped from the team at their next login. It has a CVSS v3.1 base score of 5.4 (MEDIUM).

How severe is CVE-2026-123526? +

CVE-2026-123526 has a CVSS v3.1 score of 5.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0026, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-123526? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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