CVE-2026-45720 PUBLISHED

Omni: TOCTOU race condition allows multiple concurrent uses of a single-use SAML session token

Assigner: GitHub_M
Reserved: 13.05.2026 Published: 17.09.2026 Updated: 17.09.2026

Omni manages Kubernetes on bare metal, virtual machines, or in a cloud. Prior to 1.6.6 and from 1.7.0 until 1.7.3, SAML.getSession in internal/pkg/auth/interceptor/saml.go checks SAMLAssertion.Used and marks it used in separate state operations. Concurrent requests carrying the same captured saml-session token can each observe the assertion as unused and obtain authentication as the victim before either update is visible. The attacker can invoke SAML-protected gRPC endpoints, use ConfirmPublicKey to create multiple persistent credentials tied to the victim, and generate audit entries attributed to the victim, with the resulting access potentially affecting confidentiality, integrity, and availability according to the victim's privileges. This issue is fixed in versions 1.6.6 and 1.7.3.

Metrics

CVSS Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS Score: 7

Product Status

Vendor siderolabs
Product omni
Versions
  • Version < 1.6.6 is affected
  • Version >= 1.7.0, < 1.7.3 is affected

References

Problem Types

  • CWE-294: Authentication Bypass by Capture-replay CWE
  • CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition CWE