CVE-2021-22699
Published: 26 May 2021
Summary
CVE-2021-22699 is a high-severity Improper Input Validation (CWE-20) vulnerability in Schneider-Electric Modicon M241 Firmware. Its CVSS base score is 7.5 (High).
Operationally, ranked in the top 40.9% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-9834
Vulnerability details
Improper Input Validation vulnerability exists in Modicon M241/M251 logic controllers firmware prior to V5.1.9.1 that could cause denial of service when specific crafted requests are sent to the controller over HTTP.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Security testing and developer training directly verify and enforce proper input validation, reducing exploitability of injection and malformed-data weaknesses.
Security testing and evaluation at multiple SDLC stages directly detects missing or flawed input validation, with the required remediation process ensuring fixes are applied.
Directly implements checks on information inputs to reject invalid data before processing.
Spam protection mechanisms perform filtering and detection on inbound/outbound messages, directly compensating for missing or weak input validation of unsolicited content.