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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-2021-34586"},{"url":"https://github.com/advisories/GHSA-hmwx-8xfx-mg6m"}],"sources":{"cve":[{"id":"CVE-2021-34586","title":"CODESYS V2 web server: crafted requests could trigger a null pointer dereference (DoS)","description":"In the CODESYS V2 web server prior to V1.1.9.22 crafted web server requests may cause a Null pointer dereference in the CODESYS web server and may result in a denial-of-service condition.","status":"published","published":"2021-10-26T09:55:49.885Z","modified":"2024-09-17T03:53:13.043Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-476"],"updated_at":"2026-11-02T14:33:11.244759Z"}],"euvd":[{"id":"EUVD-2021-21236","description":"In the CODESYS V2 web server prior to V1.1.9.22 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