CVE-2021-22800
CVE-2021-22800 is a high-severity vulnerability in Schneider-electric Modicon M218 Firmware with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 1% (59th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-20
- Affected product: Schneider-electric Modicon M218 Firmware
- Published:
- Last modified:
Description
A CWE-20: Improper Input Validation vulnerability exists that could cause a Denial of Service when a crafted packet is sent to the controller over network port 1105/TCP. Affected Product: Modicon M218 Logic Controller (V5.1.0.6 and prior)
Frequently asked questions
- What is CVE-2021-22800?
- A CWE-20: Improper Input Validation vulnerability exists that could cause a Denial of Service when a crafted packet is sent to the controller over network port 1105/TCP. Affected Product: Modicon M218 Logic Controller (V5.1.0.6 and prior)
- How severe is CVE-2021-22800?
- CVE-2021-22800 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2021-22800 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-22800?
- CVE-2021-22800 affects Schneider-electric Modicon M218 Firmware. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-22800?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-22800 published?
- CVE-2021-22800 was published on 2022-02-11 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:o:schneider-electric:modicon_m218_firmware:*:*:*:*:*:*:*:*
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