{"id":"CVE-2023-42441","aliases":["EUVD-2023-0274","GHSA-3hg2-r75x-g69m","PYSEC-2023-305"],"status":"published","title":"Vyper has incorrect re-entrancy lock when key is empty string","description":"Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). Starting in version 0.2.9 and prior to version 0.3.10, locks of the type `@nonreentrant(\"\")` or `@nonreentrant('')` do not produce reentrancy checks at runtime. This issue is fixed in version 0.3.10. As a workaround, ensure the lock name is a non-empty string.","severity":{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00514,"percentile":0.44059,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-667","CWE-833"],"published":"2023-09-18T19:20:55Z","modified":"2026-10-28T02:30:35Z","fixes":[{"ecosystem":"PyPI","package":"vyper","fixed_in":["0.3.10"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"vyper","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0.2.9"},{"fixed":"0.3.10"}]}]},{"source":"osv","ecosystem":"PyPI","package":"vyper","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0.2.9"},{"fixed":"0.3.10"}]}],"versions":["0.2.10","0.2.11","0.2.12","0.2.13","0.2.14","0.2.15","0.2.16","0.2.9","0.3.0","0.3.1","0.3.10rc1","0.3.10rc2","0.3.10rc3","0.3.10rc4","0.3.10rc5","0.3.2","0.3.3","0.3.4","0.3.5","0.3.6","0.3.7","0.3.8","0.3.9"]},{"source":"osv","ecosystem":"PyPI","package":"vyper","ranges":[{"type":"GIT","events":[{"introduced":"0"},{"fixed":"0b740280c1e3c5528a20d47b29831948ddcc6d83"}]},{"type":"ECOSYSTEM","events":[{"introduced":"0.2.9"},{"fixed":"0.3.10"}]}],"versions":["0.2.10","0.2.11","0.2.12","0.2.13","0.2.14","0.2.15","0.2.16","0.2.9","0.3.0","0.3.1","0.3.10rc1","0.3.10rc2","0.3.10rc3","0.3.10rc4","0.3.10rc5","0.3.2","0.3.3","0.3.4","0.3.5","0.3.6","0.3.7","0.3.8","0.3.9"]}],"products":[{"vendor":"vyperlang","product":"vyper"}],"references":[{"url":"https://github.com/vyperlang/vyper/security/advisories/GHSA-3hg2-r75x-g69m","tags":["x_refsource_CONFIRM","x_transferred","Exploit","Patch","Vendor Advisory","advisory","web"]},{"url":"https://github.com/vyperlang/vyper/pull/3605","tags":["x_refsource_MISC","x_transferred","Issue Tracking","Patch","fix","web"]},{"url":"https://github.com/vyperlang/vyper/commit/0b740280c1e3c5528a20d47b29831948ddcc6d83","tags":["x_refsource_MISC","x_transferred","Patch","fix","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-42441","tags":["advisory"]},{"url":"https://github.com/pypa/advisory-database/tree/main/vulns/vyper/PYSEC-2023-305.yaml","tags":["web"]},{"url":"https://github.com/advisories/GHSA-3hg2-r75x-g69m"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/42xxx/CVE-2023-42441.json","tags":["advisory"]},{"url":"https://github.com/vyperlang/vyper","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2023-42441","title":"Vyper has incorrect re-entrancy lock when key is empty string","description":"Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). Starting in version 0.2.9 and prior to version 0.3.10, locks of the type `@nonreentrant(\"\")` or `@nonreentrant('')` do not produce reentrancy checks at runtime. This issue is fixed in version 0.3.10. As a workaround, ensure the lock name is a non-empty string.","status":"published","published":"2023-09-18T20:19:26.086Z","modified":"2024-09-24T18:58:08.589Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-833"],"updated_at":"2026-11-02T14:35:17.812395Z"}],"euvd":[{"id":"EUVD-2023-0274","description":"Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). Starting in version 0.2.9 and prior to version 0.3.10, locks of the type `@nonreentrant(\"\")` or `@nonreentrant('')` do not produce reentrancy checks at runtime. This issue is fixed in version 0.3.10. As a workaround, ensure the lock name is a non-empty string.","status":"published","published":"2023-09-18T20:19:26Z","modified":"2024-09-24T18:58:08Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"updated_at":"2026-11-03T00:28:14.929509Z"}],"ghsa":[{"id":"GHSA-3hg2-r75x-g69m","title":"Vyper has incorrect re-entrancy lock when key is empty string","description":"### Impact\n\nLocks of the type `@nonreentrant(\"\")` or `@nonreentrant('')` do not produce reentrancy checks at runtime.\n\n```Vyper\n@nonreentrant(\"\") # unprotected\n@external\ndef bar():\n    pass\n\n@nonreentrant(\"lock\") # protected\n@external\ndef foo():\n    pass\n```\n### Patches\n\nPatched in #3605\n\n### Workarounds\n\nThe lock name should be a non-empty string.\n\n### References\n_Are there any links users can visit to find out more?_\n","status":"published","published":"2023-09-18T19:20:55Z","modified":"2024-11-22T20:35:08Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-667","CWE-833"],"updated_at":"2026-11-02T14:38:22.774145Z"}],"nvd":[{"id":"CVE-2023-42441","description":"Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). Starting in version 0.2.9 and prior to version 0.3.10, locks of the type `@nonreentrant(\"\")` or `@nonreentrant('')` do not produce reentrancy checks at runtime. This issue is fixed in version 0.3.10. As a workaround, ensure the lock name is a non-empty string.","status":"published","published":"2023-09-18T21:16:09.75Z","modified":"2026-06-17T06:23:50.14Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","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:L/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-833","CWE-667"],"updated_at":"2026-11-02T14:08:29.595868Z"}],"osv":[{"id":"CVE-2023-42441","title":"Vyper has incorrect re-entrancy lock when key is empty string","description":"Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). Starting in version 0.2.9 and prior to version 0.3.10, locks of the type `@nonreentrant(\"\")` or `@nonreentrant('')` do not produce reentrancy checks at runtime. This issue is fixed in version 0.3.10. As a workaround, ensure the lock name is a non-empty string.","status":"published","published":"2023-09-18T20:19:26.086Z","modified":"2026-10-28T02:30:35.567176931Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-833"],"updated_at":"2026-11-02T15:44:33.792101Z"},{"id":"GHSA-3hg2-r75x-g69m","title":"Vyper has incorrect re-entrancy lock when key is empty string","description":"### Impact\n\nLocks of the type `@nonreentrant(\"\")` or `@nonreentrant('')` do not produce reentrancy checks at runtime.\n\n```Vyper\n@nonreentrant(\"\") # unprotected\n@external\ndef bar():\n    pass\n\n@nonreentrant(\"lock\") # protected\n@external\ndef foo():\n    pass\n```\n### Patches\n\nPatched in #3605\n\n### Workarounds\n\nThe lock name should be a non-empty string.\n\n### References\n_Are there any links users can visit to find out more?_\n","status":"published","published":"2023-09-18T19:20:55Z","modified":"2026-09-10T03:50:03.191650148Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-667","CWE-833"],"updated_at":"2026-11-02T15:46:35.747385Z"},{"id":"PYSEC-2023-305","description":"Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). Starting in version 0.2.9 and prior to version 0.3.10, locks of the type `@nonreentrant(\"\")` or `@nonreentrant('')` do not produce reentrancy checks at runtime. This issue is fixed in version 0.3.10. As a workaround, ensure the lock name is a non-empty string.","status":"published","published":"2023-09-18T21:16:00Z","modified":"2024-11-21T14:57:14.248607Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:52:53.837392Z"}]}}