{"id":"CVE-2023-34234","aliases":["EUVD-2023-1704","GHSA-5h3x-9wvq-w4m2"],"status":"published","title":"Governor proposal creation may be blocked by frontrunning in OpenZeppelin","description":"OpenZeppelin Contracts is a library for smart contract development. By frontrunning the creation of a proposal, an attacker can become the proposer and gain the ability to cancel it. The attacker can do this repeatedly to try to prevent a proposal from being proposed at all. This impacts the `Governor` contract in v4.9.0 only, and the `GovernorCompatibilityBravo` contract since v4.3.0. This problem has been patched in 4.9.1 by introducing opt-in frontrunning protection. Users are advised to upgrade. Users unable to upgrade may submit the proposal creation transaction to an endpoint with frontrunning protection as a workaround.","severity":{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00595,"percentile":0.48922,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-862"],"published":"2023-06-07T17:06:10Z","modified":"2026-10-28T02:30:38Z","fixes":[{"ecosystem":"npm","package":"@openzeppelin/contracts","fixed_in":["4.9.1"],"sources":["ghsa","osv"]},{"ecosystem":"npm","package":"@openzeppelin/contracts-upgradeable","fixed_in":["4.9.1"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"@openzeppelin/contracts","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.3.0"},{"fixed":"4.9.1"}]}]},{"source":"ghsa","ecosystem":"npm","package":"@openzeppelin/contracts-upgradeable","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.3.0"},{"fixed":"4.9.1"}]}]},{"source":"osv","ecosystem":"npm","package":"@openzeppelin/contracts","ranges":[{"type":"SEMVER","events":[{"introduced":"4.3.0"},{"fixed":"4.9.1"}]}]},{"source":"osv","ecosystem":"npm","package":"@openzeppelin/contracts-upgradeable","ranges":[{"type":"SEMVER","events":[{"introduced":"4.3.0"},{"fixed":"4.9.1"}]}]}],"products":[{"vendor":"openzeppelin","product":"contracts"},{"vendor":"openzeppelin","product":"contracts_upgradeable"},{"vendor":"openzeppelin","product":"openzeppelin-contracts"}],"references":[{"url":"https://github.com/OpenZeppelin/openzeppelin-contracts/security/advisories/GHSA-5h3x-9wvq-w4m2","tags":["x_refsource_CONFIRM","x_transferred","Vendor Advisory","advisory","web"]},{"url":"https://github.com/OpenZeppelin/openzeppelin-contracts/commit/d9474327a492f9f310f31bc53f38dbea56ed9a57","tags":["x_refsource_MISC","x_transferred","Patch","fix","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-34234","tags":["advisory"]},{"url":"https://github.com/OpenZeppelin/openzeppelin-contracts/releases/tag/v4.9.1","tags":["web"]},{"url":"https://github.com/OpenZeppelin/openzeppelin-contracts-upgradeable/commit/66f390fa516b550838e2c2f65132b5bc2afe1ced","tags":["web"]},{"url":"https://github.com/advisories/GHSA-5h3x-9wvq-w4m2"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/34xxx/CVE-2023-34234.json","tags":["advisory"]},{"url":"https://github.com/OpenZeppelin/openzeppelin-contracts","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2023-34234","title":"Governor proposal creation may be blocked by frontrunning in OpenZeppelin","description":" OpenZeppelin Contracts is a library for smart contract development. By frontrunning the creation of a proposal, an attacker can become the proposer and gain the ability to cancel it. The attacker can do this repeatedly to try to prevent a proposal from being proposed at all. This impacts the `Governor` contract in v4.9.0 only, and the `GovernorCompatibilityBravo` contract since v4.3.0. This problem has been patched in 4.9.1 by introducing opt-in frontrunning protection. Users are advised to upgrade. Users unable to upgrade may submit the proposal creation transaction to an endpoint with frontrunning protection as a workaround.","status":"published","published":"2023-06-07T17:06:10.154Z","modified":"2025-02-06T16:55:49.744Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"cna"}],"cwes":["CWE-862"],"updated_at":"2026-11-02T14:35:35.912488Z"}],"euvd":[{"id":"EUVD-2023-1704","description":" OpenZeppelin Contracts is a library for smart contract development. By frontrunning the creation of a proposal, an attacker can become the proposer and gain the ability to cancel it. The attacker can do this repeatedly to try to prevent a proposal from being proposed at all. This impacts the `Governor` contract in v4.9.0 only, and the `GovernorCompatibilityBravo` contract since v4.3.0. This problem has been patched in 4.9.1 by introducing opt-in frontrunning protection. Users are advised to upgrade. Users unable to upgrade may submit the proposal creation transaction to an endpoint with frontrunning protection as a workaround.","status":"published","published":"2023-06-07T17:06:10Z","modified":"2025-02-06T16:55:49Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium"}],"updated_at":"2026-11-03T00:04:03.312509Z"}],"ghsa":[{"id":"GHSA-5h3x-9wvq-w4m2","title":"OpenZeppelin Contracts's governor proposal creation may be blocked by frontrunning","description":"### Impact\n\nBy frontrunning the creation of a proposal, an attacker can become the proposer and gain the ability to cancel it. The attacker can do this repeatedly to try to prevent a proposal from being proposed at all.\n\nThis impacts the `Governor` contract in v4.9.0 only, and the `GovernorCompatibilityBravo` contract since v4.3.0.\n\n### Patches\n\nThe problem has been patched in 4.9.1 by introducing opt-in frontrunning protection.\n\n### Workarounds\n\nSubmit the proposal creation transaction to an endpoint with frontrunning protection.\n\n### Credit\n\nReported by Lior Abadi and Joaquin Pereyra from Coinspect.\n\n### References\n\nhttps://www.coinspect.com/openzeppelin-governor-dos/","status":"published","published":"2023-06-08T18:03:11Z","modified":"2023-11-27T21:30:52Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium"}],"cwes":["CWE-862"],"updated_at":"2026-11-02T14:37:22.840002Z"}],"nvd":[{"id":"CVE-2023-34234","description":" OpenZeppelin Contracts is a library for smart contract development. By frontrunning the creation of a proposal, an attacker can become the proposer and gain the ability to cancel it. The attacker can do this repeatedly to try to prevent a proposal from being proposed at all. This impacts the `Governor` contract in v4.9.0 only, and the `GovernorCompatibilityBravo` contract since v4.3.0. This problem has been patched in 4.9.1 by introducing opt-in frontrunning protection. Users are advised to upgrade. Users unable to upgrade may submit the proposal creation transaction to an endpoint with frontrunning protection as a workaround.","status":"published","published":"2023-06-07T18:15:09.977Z","modified":"2026-06-17T06:03:11.14Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"secondary"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"primary"}],"cwes":["CWE-862"],"updated_at":"2026-11-02T14:08:05.329837Z"}],"osv":[{"id":"CVE-2023-34234","title":"Governor proposal creation may be blocked by frontrunning in OpenZeppelin","description":" OpenZeppelin Contracts is a library for smart contract development. By frontrunning the creation of a proposal, an attacker can become the proposer and gain the ability to cancel it. The attacker can do this repeatedly to try to prevent a proposal from being proposed at all. This impacts the `Governor` contract in v4.9.0 only, and the `GovernorCompatibilityBravo` contract since v4.3.0. This problem has been patched in 4.9.1 by introducing opt-in frontrunning protection. Users are advised to upgrade. Users unable to upgrade may submit the proposal creation transaction to an endpoint with frontrunning protection as a workaround.","status":"published","published":"2023-06-07T17:06:10.154Z","modified":"2026-10-28T02:30:38.396532491Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium"}],"cwes":["CWE-862"],"updated_at":"2026-11-02T15:44:32.116263Z"},{"id":"GHSA-5h3x-9wvq-w4m2","title":"OpenZeppelin Contracts's governor proposal creation may be blocked by frontrunning","description":"### Impact\n\nBy frontrunning the creation of a proposal, an attacker can become the proposer and gain the ability to cancel it. The attacker can do this repeatedly to try to prevent a proposal from being proposed at all.\n\nThis impacts the `Governor` contract in v4.9.0 only, and the `GovernorCompatibilityBravo` contract since v4.3.0.\n\n### Patches\n\nThe problem has been patched in 4.9.1 by introducing opt-in frontrunning protection.\n\n### Workarounds\n\nSubmit the proposal creation transaction to an endpoint with frontrunning protection.\n\n### Credit\n\nReported by Lior Abadi and Joaquin Pereyra from Coinspect.\n\n### References\n\nhttps://www.coinspect.com/openzeppelin-governor-dos/","status":"published","published":"2023-06-08T18:03:11Z","modified":"2026-09-10T03:50:02.116353126Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium"}],"cwes":["CWE-862"],"updated_at":"2026-11-02T15:46:38.553953Z"}]}}