# GPUStack: SAML callback trusts an unverified SAMLResponse, allowing authentication bypass and account takeover (CVE-2026-102894)

Source: [GitHub Advisory Database](https://github.com/advisories/GHSA-62m9-f875-rqw6) · 2026-11-10 · Security
Page: https://themorning.dev/story/gpustack-saml-callback-trusts-an-unverified-samlresponse-allowing-authentication-ab839375e61eaf75
Kind: security · Impact: high

## In brief

- GPUStack's SAML callback accepts a posted SAMLResponse without verifying it.
- The callback decodes the XML, reads NameID and attributes, resolves or provisions the user, and issues a gpustacksession JWT.
- The signature, issuer and audience checks in OneLoginSaml2Auth.processresponse() are never called, which enables authentication bypass and account takeover.

## Why it matters

Anyone who can reach a GPUStack SAML callback may be able to log in as an existing user or create one, so operators running SAML login should treat the instance as exposed until it is patched.

## CVEs

- CVE-2026-102894

## Timeline

- 2026-11-10: GitHub Advisory Database published advisory GHSA-62m9-f875-rqw6 disclosing the vulnerability

## Coverage

- [GPUStack: SAML callback trusts an unverified SAMLResponse, allowing authentication bypass and account takeover (CVE-2026-102894)](https://github.com/advisories/GHSA-62m9-f875-rqw6) — GitHub Advisory Database, 2026-11-10

Tags: gpustack, saml, authentication, vulnerability, account-takeover

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Brief generated by AI (claude-haiku-5-5) from the reporting listed under Coverage. Headlines belong to their publishers. The Morning Dev – https://themorning.dev