How severe is CVE-2026-56774?

CVE-2026-56774 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability low.

Is CVE-2026-56774 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-56774?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-56774 have an EU (EUVD) identifier?

Yes. CVE-2026-56774 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39526.

When was CVE-2026-56774 published?

CVE-2026-56774 was published on 2026-06-25.

CVE-2026-56774

CVE-2026-56774 is a medium-severity vulnerability with a CVSS 3.x base score of 5.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-639.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
CVSS v4: 5.3
EPSS exploit prediction: 0% (18th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-39526
Weakness: CWE-639
Published: 2026-06-25
Last modified: 2026-06-25

Description

Kanboard through 1.2.52, fixed in commit 928c68a, UserViewController::removeSession fails to validate the session id parameter before passing it to RememberMeSessionModel::remove, allowing authenticated users to delete other users' Remember Me sessions. Attackers can enumerate sequential session IDs and mass-invalidate persistent login sessions of any user, including administrators, forcing re-authentication and causing denial of service.

Frequently asked questions

What is CVE-2026-56774?: Kanboard through 1.2.52, fixed in commit 928c68a, UserViewController::removeSession fails to validate the session id parameter before passing it to RememberMeSessionModel::remove, allowing authenticated users to delete other users' Remember Me sessions. Attackers can enumerate sequential session IDs and mass-invalidate persistent login sessions of any user, including administrators, forcing re-authentication and causing denial of service.
How severe is CVE-2026-56774?: CVE-2026-56774 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability low.
Is CVE-2026-56774 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-56774?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-56774 have an EU (EUVD) identifier?: Yes. CVE-2026-56774 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39526.
When was CVE-2026-56774 published?: CVE-2026-56774 was published on 2026-06-25.

References

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