LinkAce: IDOR in Update Policies Allows Any Authenticated User to Overwrite Other Users' Links, Lists, Tags, and Notes

Description

LinkAce is a self-hosted archive to collect website links. Prior to 2.5.6, LinkAce contains an Insecure Direct Object Reference vulnerability in the authorization policy layer that allows any authenticated user to modify resources owned by other users. The affected resource types are links, lists, tags, and notes. Both the web UI and the REST API are vulnerable. The root cause is in the update() methods of all four model policies: LinkPolicy, LinkListPolicy, TagPolicy, and NotePolicy. Each delegates to an access-check method (e.g., userCanAccessLink()) that returns true for any resource with non-private visibility, regardless of who owns it. This means any registered user can edit any public or internal resource across the entire instance. The delete() methods in the same policy files correctly require ownership via $link->user->is($user), which confirms that update was intended to be owner-only. The same flaw exists in the API layer through AuthorizesUserApiActions::userCanUpdateModel(), which mirrors the broken visibility-only check instead of the ownership check used by userCanDeleteModel(). Bulk edit operations via BulkEditController are also affected. This vulnerability is fixed in 2.5.6.

Scores

EPSS (exploitation in 30 days)

0.22% · top 87% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: poc · Automatable: no · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.1.

Weakness

• CWE-639: Authorization Bypass Through User-Controlled Key (opens in a new tab)All about CWE-639 and its CVEs

Affected products

• Kovah · LinkAce

  • affected < 2.5.6

References (1)

• https://github.com/Kovah/LinkAce/security/advisories/GHSA-cj8f-h888-m57m (opens in a new tab)x_refsource_CONFIRMexploit

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2026-45342](https://trackcve.app/badge/CVE-2026-45342.svg)](https://trackcve.app/cve/CVE-2026-45342)

Record last updated 29 May 2026, 14:45 UTC.