CVE Feed

    Dashboard / CVE / CVE-2021-34583

    CVE-2021-34583

    Crafted web server requests may cause a heap-based buffer overflow and could therefore trigger a denial-of- service condition due to a crash in the CODESYS V2 web server prior to V1.1.9.22.

    Published:Oct 26, 2021
    Last Modified:Aug 15, 2025
    EPS:Oct 26, 2021
    EPSS Score:0.03822
    CVSS Score:7.5

    Affected Products

    Vendor
    Codesys
    Product
    Codesys
    Vendor
    Wago
    Product
    750-8202
    Vendor
    Wago
    Product
    750-8202 Firmware
    Vendor
    Wago
    Product
    750-8203
    Vendor
    Wago
    Product
    750-8203 Firmware
    Vendor
    Wago
    Product
    750-8204
    Vendor
    Wago
    Product
    750-8204 Firmware
    Vendor
    Wago
    Product
    750-8206
    Vendor
    Wago
    Product
    750-8206 Firmware
    Vendor
    Wago
    Product
    750-8207
    Vendor
    Wago
    Product
    750-8207 Firmware
    Vendor
    Wago
    Product
    750-8208
    Vendor
    Wago
    Product
    750-8208 Firmware
    Vendor
    Wago
    Product
    750-8210
    Vendor
    Wago
    Product
    750-8210 Firmware
    Vendor
    Wago
    Product
    750-8211
    Vendor
    Wago
    Product
    750-8211 Firmware
    Vendor
    Wago
    Product
    750-8212
    Vendor
    Wago
    Product
    750-8212 Firmware
    Vendor
    Wago
    Product
    750-8213
    Vendor
    Wago
    Product
    750-8213 Firmware
    Vendor
    Wago
    Product
    750-8214
    Vendor
    Wago
    Product
    750-8214 Firmware
    Vendor
    Wago
    Product
    750-8216
    Vendor
    Wago
    Product
    750-8216 Firmware
    Vendor
    Wago
    Product
    750-8217
    Vendor
    Wago
    Product
    750-8217 Firmware
    Vendor
    Wago
    Product
    750-823
    Vendor
    Wago
    Product
    750-823 Firmware
    Vendor
    Wago
    Product
    750-829
    Vendor
    Wago
    Product
    750-829 Firmware
    Vendor
    Wago
    Product
    750-831
    Vendor
    Wago
    Product
    750-831 Firmware
    Vendor
    Wago
    Product
    750-832
    Vendor
    Wago
    Product
    750-832 Firmware
    Vendor
    Wago
    Product
    750-852
    Vendor
    Wago
    Product
    750-852 Firmware
    Vendor
    Wago
    Product
    750-862
    Vendor
    Wago
    Product
    750-862 Firmware
    Vendor
    Wago
    Product
    750-880
    Vendor
    Wago
    Product
    750-880 Firmware
    Vendor
    Wago
    Product
    750-881
    Vendor
    Wago
    Product
    750-881 Firmware
    Vendor
    Wago
    Product
    750-882
    Vendor
    Wago
    Product
    750-882 Firmware
    Vendor
    Wago
    Product
    750-885
    Vendor
    Wago
    Product
    750-885 Firmware
    Vendor
    Wago
    Product
    750-889
    Vendor
    Wago
    Product
    750-889 Firmware
    Vendor
    Wago
    Product
    750-890
    Vendor
    Wago
    Product
    750-890 Firmware
    Vendor
    Wago
    Product
    750-891
    Vendor
    Wago
    Product
    750-891 Firmware
    Vendor
    Wago
    Product
    750-893
    Vendor
    Wago
    Product
    750-893 Firmware

    Exploits

    https://www.tenable.com/security/research/tra-2021-47https://www.tenable.com/security/research/tra-2021-47

    Common Attack Pattern Enumeration and Classification (CAPEC)

    CAPEC-92 Forced Integer Overflow

    Related CVEs

    CVE-2026-35227 (CVSS 8.2) — An unauthenticated remote attacker may exhaust all available TCP connections in the CODESYS Modbus TCP Server …
    CVE-2025-41700 (CVSS 7.8) — An unauthenticated attacker can trick a local user into executing arbitrary code by opening a deliberately man…
    CVE-2021-34596 (CVSS 6.5) — A crafted request may cause a read access to an uninitialized pointer in CODESYS V2 Runtime Toolkit 32 Bit ful…
    CVE-2021-34595 (CVSS 8.1) — A crafted request with invalid offsets may cause an out-of-bounds read or write access in CODESYS V2 Runtime T…
    CVE-2021-34586 (CVSS 7.5) — In the CODESYS V2 web server prior to V1.1.9.22 crafted web server requests may cause a Null pointer dereferen…
    CVE-2021-34585 (CVSS 7.5) — In the CODESYS V2 web server prior to V1.1.9.22 crafted web server requests can trigger a parser error. Since …
    CVE-2021-34584 (CVSS 9.1) — Crafted web server requests can be utilised to read partial stack or heap memory or may trigger a denial-of- s…
    CVE-2021-21869 (CVSS 7.8) — An unsafe deserialization vulnerability exists in the Engine.plugin ProfileInformation ProfileData functionali…
    CVE-2021-21868 (CVSS 7.8) — An unsafe deserialization vulnerability exists in the ObjectManager.plugin Project.get_MissingTypes() function…
    CVE-2021-21867 (CVSS 7.8) — An unsafe deserialization vulnerability exists in the ObjectManager.plugin ObjectStream.ProfileByteArray funct…

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High