CVE-2026-94456

Unauthenticated recovery of the Math.random() state behind OAuth tokens, authorization codes, client secrets and organization API keys

Published Sep 22, 2026 CVSS 3.1 · 9.1 Critical EPSS < 1% KEV · Not listed
Description
Postiz generates security-sensitive credentials using `Math.random()` instead of a cryptographically secure source. The same helper is used for OAuth access tokens, authorization codes, client secrets, organization API keys, and PKCE verifiers, meaning these credentials depend entirely on V8’s deterministic xorshift128+ PRNG state.

An unauthenticated OAuth dynamic client registration endpoint exposes freshly generated client credentials, giving attackers enough consecutive PRNG output to reconstruct that internal state. Once recovered, they can deterministically derive past and future values produced by the same generator, potentially compromising credentials belonging to other users and organizations.

Remediation

Vendor Solution

Run a Postiz release in which security-sensitive identifiers are generated from a cryptographically secure random source rather than from Math.random(). No fixed release is available at the time of writing; this advisory will record the fixed version once one is published.


Vendor Workaround

Blocking or requiring authentication on the OAuth dynamic client registration endpoint at a reverse proxy, gateway or WAF removes the anonymous bulk-sampling surface, which is the part of this issue reachable without an account. It does not make the generated values unpredictable, and it does not close the surfaces available to an authenticated user, so it narrows exposure rather than resolving it. Deployments that do not use OAuth or MCP client integrations can apply this with no loss of function.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Gitroomhq
Gitroomhq postiz-app
Vendors & Products Gitroomhq
Gitroomhq postiz-app
Type Values Removed Values Added
Description Postiz generates security-sensitive credentials using `Math.random()` instead of a cryptographically secure source. The same helper is used for OAuth access tokens, authorization codes, client secrets, organization API keys, and PKCE verifiers, meaning these credentials depend entirely on V8’s deterministic xorshift128+ PRNG state. An unauthenticated OAuth dynamic client registration endpoint exposes freshly generated client credentials, giving attackers enough consecutive PRNG output to reconstruct that internal state. Once recovered, they can deterministically derive past and future values produced by the same generator, potentially compromising credentials belonging to other users and organizations.
Title Unauthenticated recovery of the Math.random() state behind OAuth tokens, authorization codes, client secrets and organization API keys
Weaknesses CWE-330
CWE-338
CWE-341
References
Metrics cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
postiz
Published
Updated
Sep 22, 2026, 6:11 PM
Reserved
Sep 21, 2026, 5:11 PM
Status
Awaiting Analysis
Published
Sep 22, 2026, 5:17 PM
Modified
Sep 22, 2026, 7:37 PM