High severity · published Sep 17, 2026
CVE-2026-45720
Omni: TOCTOU race condition allows multiple concurrent uses of a single-use SAML session token
7.0
CVSS
0.1%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
High
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 4% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OM
omni · siderolabs
< 1.6.6; >= 1.7.0, < 1.7.3 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-45720
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-45720
github.com
https://github.com/siderolabs/omni/commit/272d3f4dd00e778b39fde09afde35575fe13ef13
github.com
https://github.com/siderolabs/omni/commit/4c4c1e2d8226914f26774a309a91595f168ee921
github.com
https://github.com/siderolabs/omni/commit/ced79da6c032d2103803eb53343d0916cc957d2a
github.com
https://github.com/siderolabs/omni/pull/2816
github.com
https://github.com/siderolabs/omni/releases/tag/v1.6.6
github.com
https://github.com/siderolabs/omni/releases/tag/v1.7.3
More from omni
7.6
CVE-2026-45726
Omni: Reader-level users can retrieve imported cluster CA keys via ResourceService
7.5
CVE-2025-61688
Omni leaks information via the API
7.5
CVE-2025-59836
Omni is Vulnerable to DoS via Empty Create/Update Resource Requests
5.4
CVE-2025-59824
Omni Wireguard SideroLink potential escape
2.7
CVE-2026-45723
Omni: Operator can traverse image-factory API paths via unsanitized `talos_version` in CreateSchematic
