{"cve":"CVE-2021-34593","nvd":{"published":"2021-10-26T10:15:08.013","modified":"2026-06-17T03:56:11.963","status":"Analyzed","description":"In CODESYS V2 Runtime Toolkit 32 Bit full and PLCWinNT prior to versions V2.4.7.56 unauthenticated crafted invalid requests may result in several denial-of-service conditions. Running PLC programs may be stopped, memory may be leaked, or further communication clients may be blocked from accessing the PLC.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-755"],"references":["http://packetstormsecurity.com/files/164716/CODESYS-2.4.7.0-Denial-Of-Service.html","http://packetstormsecurity.com/files/165874/WAGO-750-8xxx-PLC-Denial-Of-Service-User-Enumeration.html","http://seclists.org/fulldisclosure/2021/Oct/64","https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=16877&token=8faab0fc1e069f4edfca5d5aba8146139f67a175&download=","http://packetstormsecurity.com/files/164716/CODESYS-2.4.7.0-Denial-Of-Service.html"],"products":["codesys:plcwinnt","codesys:runtime_toolkit","wago:750-8202_firmware","wago:750-8203_firmware","wago:750-8204_firmware","wago:750-8206_firmware","wago:750-8207_firmware","wago:750-8208_firmware","wago:750-8210_firmware","wago:750-8211_firmware","wago:750-8212_firmware","wago:750-8213_firmware","wago:750-8214_firmware","wago:750-8216_firmware","wago:750-8217_firmware"],"source":"nvd","synced_at":"2026-10-19T21:24:39.218183596+00:00"},"epss":{"cve":"CVE-2021-34593","score":0.02662,"percentile":0.85705,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}