CVE-2026-48781
Published: 17 June 2026
Summary
CVE-2026-48781 is a critical-severity Authentication Bypass by Assumed-Immutable Data (CWE-302) vulnerability. Its CVSS base score is 9.9 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 11.2th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
OWASP Top 10 for Web (2025)
EU & UK References
No EU or UK CSIRT advisories indexed for this CVE.
Vulnerability details
Postiz is an AI social media scheduling tool. In versions prior to 2.21.8, the Skool integration callback signed an attacker-controlled JSON blob into a session-shape JWT using the application's JWT_SECRET, and the auth middleware trusted every claim in that JWT…
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without re-resolving the user from the database. Any authenticated Postiz user could forge a SUPERADMIN session and impersonate arbitrary organizations. This allowed Full Access to the following: all parts of Postiz, including users registered to the specific instance and the ability to post in the name of the victim's social media channels added to that Postiz instance. This issue has been fixed in version 2.21.8.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Authenticated users exploit flawed JWT trust in auth middleware to forge SUPERADMIN claims, directly enabling privilege escalation to full instance control.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Addresses incorrect authorization by requiring independent verification of results and an opportunity to contest before any adverse action is taken.
Periodic review and update of procedures reduces incorrect authorization implementations over time.
Supervision identifies cases where authorization logic incorrectly permits unauthorized actions.
Defining permitted attribute values and auditing modifications reduces the chance of incorrect authorization outcomes due to tampered or missing labels.
The authorization process and usage restrictions help prevent incorrect authorization for remote access types.
Establishing configuration and connection requirements helps ensure correct rather than incorrect authorization for wireless access.
Establishing connection authorization processes for mobile devices helps ensure authorization decisions are correctly implemented rather than incorrect.
Monitoring account use, notifying on changes, and reviewing accounts for compliance corrects incorrect authorization assignments.