How severe is CVE-2021-22816?

CVE-2021-22816 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-2021-22816 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-22816?

CVE-2021-22816 primarily affects Schneider-electric Scadapack 312e Firmware. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-22816?

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-2021-22816 published?

CVE-2021-22816 was published on 2022-01-28 and last updated on 2026-06-17.

CVE-2021-22816

CVE-2021-22816 is a high-severity vulnerability in Schneider-electric Scadapack 312e 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-754.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-754
Affected product: Schneider-electric Scadapack 312e Firmware
Published: 2022-01-28
Last modified: 2026-06-17

Description

A CWE-754: Improper Check for Unusual or Exceptional Conditions vulnerability exists that could cause a Denial of Service of the RTU when receiving a specially crafted request over Modbus, and the RTU is configured as a Modbus server. Affected Products: SCADAPack 312E, 313E, 314E, 330E, 333E, 334E, 337E, 350E and 357E RTUs with firmware V8.18.1 and prior

Frequently asked questions

What is CVE-2021-22816?: A CWE-754: Improper Check for Unusual or Exceptional Conditions vulnerability exists that could cause a Denial of Service of the RTU when receiving a specially crafted request over Modbus, and the RTU is configured as a Modbus server. Affected Products: SCADAPack 312E, 313E, 314E, 330E, 333E, 334E, 337E, 350E and 357E RTUs with firmware V8.18.1 and prior
How severe is CVE-2021-22816?: CVE-2021-22816 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-2021-22816 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-22816?: CVE-2021-22816 primarily affects Schneider-electric Scadapack 312e Firmware. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-22816?: 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-2021-22816 published?: CVE-2021-22816 was published on 2022-01-28 and last updated on 2026-06-17.

References

https://download.schneider-electric.com/files?p_Doc_Ref=SEVD-2021-313-01

Affected products (9)

cpe:2.3:o:schneider-electric:scadapack_312e_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:scadapack_313e_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:scadapack_314e_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:scadapack_330e_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:scadapack_333e_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:scadapack_334e_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:scadapack_337e_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:scadapack_350e_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:scadapack_357e_firmware:*:*:*:*:*:*:*:*

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