Security advisory
OpenZepplin is a library for smart contract development. In affected versions a vulnerability in TimelockController allowed an actor with the executor role to escalate privileges. Further details about the vulnerability will be disclosed at a later date. As a workaround revoke the executor role from accounts not strictly under the team's control. We recommend revoking all executors that are not also proposers. When applying this mitigation, ensure there is at least one proposer and executor remaining.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-39167
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 08:49 UTC · Revision 1
Source evidence
OpenZepplin is a library for smart contract development. In affected versions a vulnerability in TimelockController allowed an actor with the executor role to escalate privileges. Further details about the vulnerability will be disclosed at a later date. As a workaround revoke the executor role from accounts not strictly under the team's control. We recommend revoking all executors that are not also proposers. When applying this mitigation, ensure there is at least one proposer and executor remaining.
osv:CVE-2021-39167
Complete source record
{
"id": "091f0d8df388ee926ce50be4e78a8fc8a7179ba3d6288e5e1843ab922b395f9f",
"url": "https://osv.dev/vulnerability/CVE-2021-39167",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2021-39167",
"summary": "OpenZepplin is a library for smart contract development. In affected versions a vulnerability in TimelockController allowed an actor with the executor role to escalate privileges. Further details about the vulnerability will be disclosed at a later date. As a workaround revoke the executor role from accounts not strictly under the team's control. We recommend revoking all executors that are not also proposers. When applying this mitigation, ensure there is at least one proposer and executor remaining.",
"evidence": "osv:CVE-2021-39167",
"products": [],
"severity": "critical",
"structured": {
"id": "CVE-2021-39167",
"aliases": [
"CVE-2021-39167",
"GHSA-fg47-3c2x-m2wr"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/openzeppelin/openzeppelin-contracts",
"type": "GIT",
"events": [
{
"introduced": "6be5ffe54fc8982b7c1d0f45d4cb7bbd313107cd"
},
{
"fixed": "8e0296096449d9b1cd7c5631e917330635244c37"
},
{
"introduced": "a673994de5eba4305cefb8ae98ea9ad37a43efaa"
},
{
"fixed": "6edb6dd1ca43d05a762d84c688116b3327f5e490"
},
{
"fixed": "cec4f2ef57495d8b1742d62846da212515d99dd5"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:openzeppelin:contracts:*:*:*:*:*:node.js:*:*",
"range": [
{
"introduced": "3.3.0"
},
{
"fixed": "3.4.2"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:openzeppelin:contracts:*:*:*:*:*:node.js:*:*",
"range": [
{
"introduced": "4.0.0"
},
{
"fixed": "4.3.1"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "cec4f2ef57495d8b1742d62846da212515d99dd5"
}
],
"source": "REFERENCES_COMMIT"
}
]
}
}
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-39167.json"
}
}
],
"modified": "2026-10-24T10:50:25.176752024Z",
"provider": "osv",
"references": [
"https://github.com/OpenZeppelin/openzeppelin-contracts/security/advisories/GHSA-fg47-3c2x-m2wr",
"https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/CHANGELOG.md#431",
"https://github.com/OpenZeppelin/openzeppelin-contracts/commit/cec4f2ef57495d8b1742d62846da212515d99dd5"
],
"provider_metadata": {
"unresolved_ranges": [
{
"cpes": [
"cpe:2.3:a:openzeppelin:contracts:*:*:*:*:*:node.js:*:*"
],
"vendor_product": "openzeppelin:contracts",
"extracted_events": [
{
"range": [
{
"introduced": "3.3.0"
},
{
"fixed": "3.4.2"
},
{
"introduced": "4.0.0"
},
{
"fixed": "4.3.1"
}
],
"source": "CPE_RANGE"
}
]
}
]
}
},
"related_cves": [
{
"value": "CVE-2021-39167",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 442140,
"published_at": "2021-08-27T00:15:06.97+00:00"
}