{"id":"CVE-2021-34584","aliases":["EUVD-2021-21234","GHSA-j5c2-6xq9-fj5m"],"status":"published","title":"CODESYS V2 web server: crafted requests could trigger a buffer over-read (DoS)","description":"Crafted web server requests can be utilised to read partial stack or heap memory or may trigger a denial-of- service condition due to a crash in the CODESYS V2 web server prior to V1.1.9.22.","severity":{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.0108,"percentile":0.65382,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-126"],"published":"2021-10-26T09:55:46Z","modified":"2026-06-17T03:56:10Z","products":[{"vendor":"codesys","product":"codesys"},{"vendor":"codesys","product":"codesys 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Advisory"]},{"url":"https://www.tenable.com/security/research/tra-2021-47","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-34584"},{"url":"https://github.com/advisories/GHSA-j5c2-6xq9-fj5m"}],"sources":{"cve":[{"id":"CVE-2021-34584","title":"CODESYS V2 web server: crafted requests could trigger a buffer over-read (DoS)","description":"Crafted web server requests can be utilised to read partial stack or heap memory or may trigger a denial-of- service condition due to a crash in the CODESYS V2 web server prior to V1.1.9.22.","status":"published","published":"2021-10-26T09:55:46.638Z","modified":"2024-09-16T22:25:58.664Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","level":"critical","assessor":"cna"}],"cwes":["CWE-126"],"updated_at":"2026-11-02T14:33:11.244759Z"}],"euvd":[{"id":"EUVD-2021-21234","description":"Crafted web server requests can be utilised to read partial stack or heap memory or may trigger a denial-of- service condition due to a crash in the CODESYS V2 web server prior to V1.1.9.22.","status":"published","published":"2021-10-26T09:55:46Z","modified":"2024-09-16T22:25:58Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","level":"critical"}],"updated_at":"2026-11-03T00:55:02.946444Z"}],"ghsa":[{"id":"GHSA-j5c2-6xq9-fj5m","title":"Crafted web server requests can be utilised to read partial stack or heap memory or may trigger a...","description":"Crafted web server requests can be utilised to read partial stack or heap memory or may trigger a denial-of- service condition due to a crash in the CODESYS V2 web server prior to V1.1.9.22.","status":"published","published":"2022-05-24T19:18:52Z","modified":"2023-01-30T05:03:29Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","level":"critical"}],"cwes":["CWE-126"],"updated_at":"2026-11-02T14:46:50.963031Z"}],"nvd":[{"id":"CVE-2021-34584","description":"Crafted web server requests can be utilised to read partial stack or heap memory or may trigger a denial-of- service condition due to a crash in the CODESYS V2 web server prior to 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