Omni: TOCTOU race condition allows multiple concurrent uses of a single-use SAML session token
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.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-45720
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 3 Nov 2026, 06:06 UTC · Revision 1
Source evidence
Omni: TOCTOU race condition allows multiple concurrent uses of a single-use SAML session token
core-osv · Original sourcePublished 17 Sept 2026, 19:40 UTC
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.
osv:CVE-2026-45720
Complete source record
{
"id": "4c92f8eaa15ead4603d76f2f911b67c25a3dffa7c9bc2d1f658f20660cdd0cc4",
"url": "https://osv.dev/vulnerability/CVE-2026-45720",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Omni: TOCTOU race condition allows multiple concurrent uses of a single-use SAML session token",
"summary": "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.",
"evidence": "osv:CVE-2026-45720",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2026-45720",
"aliases": [
"CVE-2026-45720",
"GHSA-5x9f-6vg5-qg4m",
"GO-2026-5160"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/siderolabs/omni",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "9769f9442e302e000401e351ffd6d6fb3671a5bf"
},
{
"introduced": "5e912b14ddad86d13d9c004a9774a875e9cee108"
},
{
"fixed": "e70a16e4a226aa2f98643dbed6664edc1a5e90e7"
},
{
"fixed": "272d3f4dd00e778b39fde09afde35575fe13ef13"
},
{
"fixed": "4c4c1e2d8226914f26774a309a91595f168ee921"
},
{
"fixed": "ced79da6c032d2103803eb53343d0916cc957d2a"
}
],
"database_specific": {
"extracted_events": [
{
"range": [
{
"introduced": "0"
},
{
"fixed": "1.6.6"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
"range": [
{
"introduced": "1.7.0"
},
{
"fixed": "1.7.3"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
"range": [
{
"fixed": "272d3f4dd00e778b39fde09afde35575fe13ef13"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "4c4c1e2d8226914f26774a309a91595f168ee921"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "ced79da6c032d2103803eb53343d0916cc957d2a"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "9769f9442e302e000401e351ffd6d6fb3671a5bf"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v1.6.6"
},
{
"range": [
{
"fixed": "e70a16e4a226aa2f98643dbed6664edc1a5e90e7"
}
],
"source": "REFERENCES_TAG",
"original_tag": "v1.7.3"
}
]
}
}
],
"versions": [
"v1.6.5",
"client/v1.6.5",
"v1.7.2",
"client/v1.7.2",
"v1.7.1",
"client/v1.7.1",
"v1.7.0",
"client/v1.7.0",
"v1.7.0-beta.0",
"client/v1.7.0-beta.0",
"v1.6.4",
"client/v1.6.4",
"v1.6.3",
"client/v1.6.3",
"v1.6.2",
"client/v1.6.2",
"v1.6.1",
"client/v1.6.1",
"v1.6.0",
"client/v1.6.0",
"v1.6.0-beta.3",
"client/v1.6.0-beta.3",
"v1.6.0-beta.2",
"client/v1.6.0-beta.2",
"v1.6.0-beta.1",
"client/v1.6.0-beta.1",
"v1.6.0-beta.0",
"client/v1.6.0-beta.0",
"v1.5.0-beta.2",
"client/v1.5.0-beta.2",
"v1.5.0-beta.1",
"client/v1.5.0-beta.1",
"v1.5.0-beta.0",
"v1.4.0-beta.1",
"client/v1.4.0-beta.1",
"v1.4.0-beta.0",
"client/v1.4.0-beta.0",
"v1.3.0-beta.1",
"client/v1.3.0-beta.1",
"v1.2.0-beta.3",
"client/v1.2.0-beta.3",
"v1.2.0-beta.2",
"client/v1.2.0-beta.2",
"v1.2.0-beta.1",
"client/v1.2.0-beta.1",
"v1.2.0-beta.0",
"client/v1.2.0-beta.0",
"v1.1.0-beta.0",
"v1.0.0-beta.1",
"v1.0.0-beta.0",
"v0.52.0-beta.0",
"v0.51.0-beta.2",
"v0.51.0-beta.1",
"client/v0.51.0-beta.1",
"v0.51.0-beta.0",
"client/v0.51.0-beta.0",
"v0.50.0-beta.0",
"v0.49.0-beta.0",
"v0.48.0-beta.0",
"client/v0.48.0-beta.0",
"v0.47.0-beta.1",
"v0.47.0-beta.0",
"v0.46.0-beta.0",
"v0.45.0-beta.0",
"v0.44.0-beta.0",
"v0.43.0",
"v0.43.0-beta.0",
"v0.42.0-beta.0",
"v0.41.0-beta.0",
"v0.40.0-beta.0",
"v0.39.0-beta.0",
"v0.38.0-beta.0",
"v0.37.0-beta.0",
"v0.36.0-beta.0",
"v0.35.0-beta.0",
"v0.34.0-beta.0",
"v0.33.0-beta.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-45720.json"
}
}
],
"modified": "2026-10-28T02:30:26.189696703Z",
"provider": "osv",
"references": [
"https://github.com/siderolabs/omni/releases/tag/v1.6.6",
"https://github.com/siderolabs/omni/releases/tag/v1.7.3",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45720.json",
"https://github.com/siderolabs/omni/security/advisories/GHSA-5x9f-6vg5-qg4m",
"https://nvd.nist.gov/vuln/detail/CVE-2026-45720",
"https://github.com/siderolabs/omni/commit/272d3f4dd00e778b39fde09afde35575fe13ef13",
"https://github.com/siderolabs/omni/commit/4c4c1e2d8226914f26774a309a91595f168ee921",
"https://github.com/siderolabs/omni/commit/ced79da6c032d2103803eb53343d0916cc957d2a",
"https://github.com/siderolabs/omni/pull/2816"
],
"provider_metadata": {
"cwe_ids": [
"CWE-294",
"CWE-367"
],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45720.json"
}
},
"related_cves": [
{
"value": "CVE-2026-45720",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 492931,
"published_at": "2026-09-17T19:40:57.112+00:00"
}