CVE-2026-55064Public exploitNetwork attack vectorHinoki check available

Unauthorized project detachment via zero parent identifier

Published Aug 28, 2026 · Updated Aug 28, 2026

Missing authorization in Vikunja 2.3.0 through versions before 2.4.0 allows remote authenticated users to detach shared child projects. The update path skips Admin checks when parent_project_id is zero but always persists that value, moving the project to the root. Write access to a shared child project is sufficient; detachment breaks its hierarchy and can remove access inherited by collaborators from the parent.

CVSS severity4.3
Medium
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Missing authorization in Vikunja 2.3.0 through versions before 2.4.0 allows remote authenticated users to detach shared child projects. The update path skips Admin checks when parent_project_id is zero but always persists that value, moving the project to the root. Write access to a shared child project is sufficient; detachment breaks its hierarchy and can remove access inherited by collaborators from the parent.

The record

CVE
CVE-2026-55064
Published
Aug 28, 2026
Updated
Aug 28, 2026
Vendor
Vikunja
Product
Vikunja
Classifications
CWE-862, T1565.001
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 28, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 28, 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.

  1. Affected versionversion=>= 2.3.0, < 2.4.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Vikunja · Vikunjaversion=>= 2.3.0, < 2.4.0

Published CVSS scores

4.3GitHubCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

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.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-862Missing Authorization
T1565.001Stored Data Manipulation

Public exploit references

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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