Medium
mistral — security advisory
In OpenStack Mistral through 23.0.0, the workflow membership API lets a project that has accepted a share of another project's private workflow create a further membership naming a third project. The new membership row is created with its project_id defaulted to the accepting project rather than the original workflow owner, and thus the owner can neither see nor delete it. The third project can accept this membership (that it had not actually been granted by the owner), and then read and execute the owner's private workflow; only the accepting (not the owning) project can later revoke that access.
- Products
- mistral
- Affected versions
- 1.0.0-1, 1.0.0-4, 10.0.0-0ubuntu0.20.04.1, 10.0.0~b1~git2019121815.bc46b29f-0ubuntu1, 10.0.0~b2~git2020020609.5b5576dd-0ubuntu1, 10.0.0~b3~git2020032611.8a5d35ac-0ubuntu1, 10.0.0~b3~git2020041013.a7da00d7-0ubuntu1, 13.0.0+git2021120910.b2d6de56-0ubuntu1, 13.0.0+git2022030313.55bb2564-0ubuntu1, 13.0.0-0ubuntu1, 14.0.0-0ubuntu1, 14.0.0-0ubuntu1.1, 17.0.0-0ubuntu1, 18.0.0~rc1-0ubuntu1, 18.0.1-0ubuntu1, 18.0.1-0ubuntu1.1, 2.0.0-1, 2.0.0-1ubuntu2, 2.0.0-1ubuntu2+esm1, 2.0.0~b3-3, 2.0.0~rc1-1, 2.0.0~rc2-1, 21.0.0+git20260106.10.420677c8-0ubuntu1, 21.0.0-0ubuntu1, 22.0.0+git20260814.61.b4aeb55-0ubuntu1, 22.0.0-0ubuntu1, 22.0.0-0ubuntu1.1, 22.0.0-0ubuntu2, 23.0.0-0ubuntu1, 23.0.0~rc1-0ubuntu1, 5.0.0-0ubuntu1, 6.0.0-0ubuntu1, 6.0.0-0ubuntu1.1, 6.0.0-0ubuntu1.1+esm1, 6.0.0~b1-0ubuntu1, 6.0.0~b1-0ubuntu2, 6.0.0~b2-0ubuntu1, 6.0.0~rc1-0ubuntu1, 9.0.0-0ubuntu1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-93861
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 03:33 UTC · Revision 1
Source evidence
In OpenStack Mistral through 23.0.0, the workflow membership API lets a project that has accepted a share of another project's private workflow create a further membership naming a third project. The new membership row is created with its project_id defaulted to the accepting project rather than the original workflow owner, and thus the owner can neither see nor delete it. The third project can accept this membership (that it had not actually been granted by the owner), and then read and execute the owner's private workflow; only the accepting (not the owning) project can later revoke that access.
osv:UBUNTU-CVE-2026-93861
mistral
Fixed versions: Not specified
mistral
Fixed versions: Not specified
mistral
Fixed versions: Not specified
mistral
Fixed versions: Not specified
mistral
Fixed versions: Not specified
mistral
Fixed versions: Not specified
mistral
Fixed versions: Not specified
Complete source record
{
"id": "eea86ad371ba3b8eee4be2f7e5d1f36614b90d9de722f301c6032d8735a2a3c7",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-93861",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2026-93861",
"summary": "In OpenStack Mistral through 23.0.0, the workflow membership API lets a project that has accepted a share of another project's private workflow create a further membership naming a third project. The new membership row is created with its project_id defaulted to the accepting project rather than the original workflow owner, and thus the owner can neither see nor delete it. The third project can accept this membership (that it had not actually been granted by the owner), and then read and execute the owner's private workflow; only the accepting (not the owning) project can later revoke that access.",
"evidence": "osv:UBUNTU-CVE-2026-93861",
"products": [
{
"name": {
"value": "mistral",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1.0.0-1",
"evidence": "/affected/0/versions"
},
{
"value": "1.0.0-4",
"evidence": "/affected/0/versions"
},
{
"value": "2.0.0~b3-3",
"evidence": "/affected/0/versions"
},
{
"value": "2.0.0~rc1-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.0.0~rc2-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.0.0-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.0.0-1ubuntu2",
"evidence": "/affected/0/versions"
},
{
"value": "2.0.0-1ubuntu2+esm1",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "mistral",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "5.0.0-0ubuntu1",
"evidence": "/affected/1/versions"
},
{
"value": "6.0.0~b1-0ubuntu1",
"evidence": "/affected/1/versions"
},
{
"value": "6.0.0~b1-0ubuntu2",
"evidence": "/affected/1/versions"
},
{
"value": "6.0.0~b2-0ubuntu1",
"evidence": "/affected/1/versions"
},
{
"value": "6.0.0~rc1-0ubuntu1",
"evidence": "/affected/1/versions"
},
{
"value": "6.0.0-0ubuntu1",
"evidence": "/affected/1/versions"
},
{
"value": "6.0.0-0ubuntu1.1",
"evidence": "/affected/1/versions"
},
{
"value": "6.0.0-0ubuntu1.1+esm1",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "mistral",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "9.0.0-0ubuntu1",
"evidence": "/affected/2/versions"
},
{
"value": "10.0.0~b1~git2019121815.bc46b29f-0ubuntu1",
"evidence": "/affected/2/versions"
},
{
"value": "10.0.0~b2~git2020020609.5b5576dd-0ubuntu1",
"evidence": "/affected/2/versions"
},
{
"value": "10.0.0~b3~git2020032611.8a5d35ac-0ubuntu1",
"evidence": "/affected/2/versions"
},
{
"value": "10.0.0~b3~git2020041013.a7da00d7-0ubuntu1",
"evidence": "/affected/2/versions"
},
{
"value": "10.0.0-0ubuntu0.20.04.1",
"evidence": "/affected/2/versions"
}
]
},
{
"name": {
"value": "mistral",
"evidence": "/affected/3/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "13.0.0-0ubuntu1",
"evidence": "/affected/3/versions"
},
{
"value": "13.0.0+git2021120910.b2d6de56-0ubuntu1",
"evidence": "/affected/3/versions"
},
{
"value": "13.0.0+git2022030313.55bb2564-0ubuntu1",
"evidence": "/affected/3/versions"
},
{
"value": "14.0.0-0ubuntu1",
"evidence": "/affected/3/versions"
},
{
"value": "14.0.0-0ubuntu1.1",
"evidence": "/affected/3/versions"
}
]
},
{
"name": {
"value": "mistral",
"evidence": "/affected/4/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "17.0.0-0ubuntu1",
"evidence": "/affected/4/versions"
},
{
"value": "18.0.0~rc1-0ubuntu1",
"evidence": "/affected/4/versions"
},
{
"value": "18.0.1-0ubuntu1",
"evidence": "/affected/4/versions"
},
{
"value": "18.0.1-0ubuntu1.1",
"evidence": "/affected/4/versions"
}
]
},
{
"name": {
"value": "mistral",
"evidence": "/affected/5/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "22.0.0-0ubuntu1",
"evidence": "/affected/5/versions"
},
{
"value": "22.0.0-0ubuntu2",
"evidence": "/affected/5/versions"
},
{
"value": "22.0.0+git20260814.61.b4aeb55-0ubuntu1",
"evidence": "/affected/5/versions"
},
{
"value": "23.0.0~rc1-0ubuntu1",
"evidence": "/affected/5/versions"
},
{
"value": "23.0.0-0ubuntu1",
"evidence": "/affected/5/versions"
}
]
},
{
"name": {
"value": "mistral",
"evidence": "/affected/6/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "21.0.0-0ubuntu1",
"evidence": "/affected/6/versions"
},
{
"value": "21.0.0+git20260106.10.420677c8-0ubuntu1",
"evidence": "/affected/6/versions"
},
{
"value": "22.0.0-0ubuntu1",
"evidence": "/affected/6/versions"
},
{
"value": "22.0.0-0ubuntu1.1",
"evidence": "/affected/6/versions"
}
]
}
],
"severity": "medium",
"structured": {
"id": "UBUNTU-CVE-2026-93861",
"aliases": [
"UBUNTU-CVE-2026-93861"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N"
},
{
"type": "Ubuntu",
"score": "medium"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "mistral",
"purl": "pkg:deb/ubuntu/mistral?arch=source&distro=esm-apps%2Fxenial",
"ecosystem": "Ubuntu:Pro:16.04:LTS"
},
"versions": [
"1.0.0-1",
"1.0.0-4",
"2.0.0~b3-3",
"2.0.0~rc1-1",
"2.0.0~rc2-1",
"2.0.0-1",
"2.0.0-1ubuntu2",
"2.0.0-1ubuntu2+esm1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-93861.json"
},
"ecosystem_specific": {
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{
"binary_name": "mistral-api",
"binary_version": "2.0.0-1ubuntu2+esm1"
},
{
"binary_name": "mistral-common",
"binary_version": "2.0.0-1ubuntu2+esm1"
},
{
"binary_name": "mistral-engine",
"binary_version": "2.0.0-1ubuntu2+esm1"
},
{
"binary_name": "mistral-executor",
"binary_version": "2.0.0-1ubuntu2+esm1"
},
{
"binary_name": "python-mistral",
"binary_version": "2.0.0-1ubuntu2+esm1"
}
]
}
},
{
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{
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}
]
}
],
"package": {
"name": "mistral",
"purl": "pkg:deb/ubuntu/mistral?arch=source&distro=esm-apps%2Fbionic",
"ecosystem": "Ubuntu:Pro:18.04:LTS"
},
"versions": [
"5.0.0-0ubuntu1",
"6.0.0~b1-0ubuntu1",
"6.0.0~b1-0ubuntu2",
"6.0.0~b2-0ubuntu1",
"6.0.0~rc1-0ubuntu1",
"6.0.0-0ubuntu1",
"6.0.0-0ubuntu1.1",
"6.0.0-0ubuntu1.1+esm1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-93861.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "mistral-api",
"binary_version": "6.0.0-0ubuntu1.1+esm1"
},
{
"binary_name": "mistral-common",
"binary_version": "6.0.0-0ubuntu1.1+esm1"
},
{
"binary_name": "mistral-engine",
"binary_version": "6.0.0-0ubuntu1.1+esm1"
},
{
"binary_name": "mistral-event-engine",
"binary_version": "6.0.0-0ubuntu1.1+esm1"
},
{
"binary_name": "mistral-executor",
"binary_version": "6.0.0-0ubuntu1.1+esm1"
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"10.0.0~b2~git2020020609.5b5576dd-0ubuntu1",
"10.0.0~b3~git2020032611.8a5d35ac-0ubuntu1",
"10.0.0~b3~git2020041013.a7da00d7-0ubuntu1",
"10.0.0-0ubuntu0.20.04.1"
],
"database_specific": {
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},
"ecosystem_specific": {
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{
"binary_name": "mistral-common",
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},
{
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"binary_version": "10.0.0-0ubuntu0.20.04.1"
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{
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{
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{
"binary_name": "python3-mistral",
"binary_version": "10.0.0-0ubuntu0.20.04.1"
}
]
}
},
{
"ranges": [
{
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],
"package": {
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"ecosystem": "Ubuntu:22.04:LTS"
},
"versions": [
"13.0.0-0ubuntu1",
"13.0.0+git2021120910.b2d6de56-0ubuntu1",
"13.0.0+git2022030313.55bb2564-0ubuntu1",
"14.0.0-0ubuntu1",
"14.0.0-0ubuntu1.1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-93861.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "mistral-api",
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},
{
"binary_name": "mistral-common",
"binary_version": "14.0.0-0ubuntu1.1"
},
{
"binary_name": "mistral-engine",
"binary_version": "14.0.0-0ubuntu1.1"
},
{
"binary_name": "mistral-event-engine",
"binary_version": "14.0.0-0ubuntu1.1"
},
{
"binary_name": "mistral-executor",
"binary_version": "14.0.0-0ubuntu1.1"
},
{
"binary_name": "python3-mistral",
"binary_version": "14.0.0-0ubuntu1.1"
}
]
}
},
{
"ranges": [
{
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{
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}
]
}
],
"package": {
"name": "mistral",
"purl": "pkg:deb/ubuntu/mistral?arch=source&distro=noble",
"ecosystem": "Ubuntu:24.04:LTS"
},
"versions": [
"17.0.0-0ubuntu1",
"18.0.0~rc1-0ubuntu1",
"18.0.1-0ubuntu1",
"18.0.1-0ubuntu1.1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-93861.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "mistral-api",
"binary_version": "18.0.1-0ubuntu1.1"
},
{
"binary_name": "mistral-common",
"binary_version": "18.0.1-0ubuntu1.1"
},
{
"binary_name": "mistral-engine",
"binary_version": "18.0.1-0ubuntu1.1"
},
{
"binary_name": "mistral-event-engine",
"binary_version": "18.0.1-0ubuntu1.1"
},
{
"binary_name": "mistral-executor",
"binary_version": "18.0.1-0ubuntu1.1"
},
{
"binary_name": "python3-mistral",
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}
]
}
},
{
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{
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{
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}
]
}
],
"package": {
"name": "mistral",
"purl": "pkg:deb/ubuntu/mistral?arch=source&distro=stonking",
"ecosystem": "Ubuntu:26.10"
},
"versions": [
"22.0.0-0ubuntu1",
"22.0.0-0ubuntu2",
"22.0.0+git20260814.61.b4aeb55-0ubuntu1",
"23.0.0~rc1-0ubuntu1",
"23.0.0-0ubuntu1"
],
"database_specific": {
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},
"ecosystem_specific": {
"binaries": [
{
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},
{
"binary_name": "mistral-common",
"binary_version": "23.0.0-0ubuntu1"
},
{
"binary_name": "mistral-engine",
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},
{
"binary_name": "mistral-event-engine",
"binary_version": "23.0.0-0ubuntu1"
},
{
"binary_name": "mistral-executor",
"binary_version": "23.0.0-0ubuntu1"
},
{
"binary_name": "python3-mistral",
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}
]
}
},
{
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{
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{
"introduced": "0"
}
]
}
],
"package": {
"name": "mistral",
"purl": "pkg:deb/ubuntu/mistral?arch=source&distro=resolute",
"ecosystem": "Ubuntu:26.04:LTS"
},
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"21.0.0+git20260106.10.420677c8-0ubuntu1",
"22.0.0-0ubuntu1",
"22.0.0-0ubuntu1.1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-93861.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "mistral-api",
"binary_version": "22.0.0-0ubuntu1.1"
},
{
"binary_name": "mistral-common",
"binary_version": "22.0.0-0ubuntu1.1"
},
{
"binary_name": "mistral-engine",
"binary_version": "22.0.0-0ubuntu1.1"
},
{
"binary_name": "mistral-event-engine",
"binary_version": "22.0.0-0ubuntu1.1"
},
{
"binary_name": "mistral-executor",
"binary_version": "22.0.0-0ubuntu1.1"
},
{
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}
]
}
}
],
"modified": "2026-10-17T13:01:18.731433944Z",
"provider": "osv",
"upstream": [
"CVE-2026-93861"
],
"references": [
"https://ubuntu.com/security/CVE-2026-93861",
"https://www.cve.org/CVERecord?id=CVE-2026-93861",
"https://launchpad.net/bugs/2161277",
"https://security.openstack.org/ossa/OSSA-2026-044.html"
]
},
"related_cves": [
{
"value": "CVE-2026-93861",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 361615,
"published_at": "2026-10-08T18:18:00+00:00"
}