Vulnerability details

Reliance on Cookies without Validation and Integrity Checking vulnerability in ash-project ash_admin lets an attacker who controls a sibling subdomain rebind an admin's session to a different actor, tenant, or authorization mode. AshAdmin's client JavaScript read its state cookies (tenant, actor_resource, actor_primary_key, actor_action, actor_domain, actor_authorizing, actor_paused) by matching the cookie name with an unanchored regular expression (new RegExp(name + "=([^;]+)")) against the whole document.cookie. Any cookie whose name merely ends with the requested name therefore matches, and whichever is serialized first wins. Because cookies are shared across a registrable domain, a compromised sibling subdomain can set a shadowing cookie (for example xactor_authorizing) with Domain=.example.com that flows unvalidated into the admin's LiveSocket connect params. The fix matches cookie names by exact equality. This issue affects ash_admin: from 0.9.1 before 1.3.1.

• https://cna.erlef.org/cves/CVE-2026-75757.html related
• https://osv.dev/vulnerability/EEF-CVE-2026-75757 related
• https://github.com/ash-project/ash_admin/commit/e93a3408a85035e1f90275d02bc2470c96095e56 patch
• https://github.com/ash-project/ash_admin/security/advisories/GHSA-3259-55fp-w94j vendor-advisoryrelated