CVE-2021-22786

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-02-01 · updated 2026-06-17
Weakness: CWE-200

Description

A CWE-200: Information Exposure vulnerability exists that could cause the exposure of sensitive information stored on the memory of the controller when communicating over the Modbus TCP protocol. Affected Products: Modicon M340 CPU (part numbers BMXP34*) (Versions prior to V3.30), Modicon M580 CPU (part numbers BMEP* and BMEH*) (Versions prior to SV3.20), Modicon MC80 (BMKC80) (Versions prior to V1.6), Modicon M580 CPU Safety (part numbers BMEP58*S and BMEH58*S) (All Versions), Modicon Momentum MDI (171CBU*) (Versions prior to V2.3), Legacy Modicon Quantum (All Versions)

Affected products

Schneider-Electric Modicon M340 Bmxp341000 Firmware: before 3.40 — fixed in 3.40
Schneider-Electric Modicon M340 Bmxp342000 Firmware: before 3.40 — fixed in 3.40
Schneider-Electric Modicon M340 Bmxp3420102 Firmware: before 3.40 — fixed in 3.40
Schneider-Electric Modicon M340 Bmxp342010 Firmware: before 3.40 — fixed in 3.40
Schneider-Electric Modicon M340 Bmxp342020 Firmware: before 3.40 — fixed in 3.40
Schneider-Electric Modicon M340 Bmxp342020H Firmware: before 3.40 — fixed in 3.40
Schneider-Electric Modicon M340 Bmxp3420302 Firmware: before 3.40 — fixed in 3.40
Schneider-Electric Modicon M340 Bmxp3420302H Firmware: before 3.40 — fixed in 3.40
Schneider-Electric Modicon M340 Bmxp342030 Firmware: before 3.40 — fixed in 3.40
Schneider-Electric Modicon M340 Bmxp342030H Firmware: before 3.40 — fixed in 3.40
Schneider-Electric Modicon M580 Bmeh582040 Firmware: through 3.20
Schneider-Electric Modicon M580 Bmeh582040C Firmware: through 3.20
Schneider-Electric Modicon M580 Bmeh582040S Firmware: through 3.20
Schneider-Electric Modicon M580 Bmeh584040 Firmware: through 3.20
Schneider-Electric Modicon M580 Bmeh584040C Firmware: through 3.20
Schneider-Electric Modicon M580 Bmeh584040S Firmware: through 3.20
Schneider-Electric Modicon M580 Bmeh586040 Firmware: through 3.20
Schneider-Electric Modicon M580 Bmeh586040C Firmware: through 3.20
Schneider-Electric Modicon M580 Bmeh586040S Firmware: through 3.20
Schneider-Electric Modicon M580 Bmep581020 Firmware: through 3.20
Schneider-Electric Modicon M580 Bmep581020H Firmware: through 3.20
Schneider-Electric Modicon M580 Bmep582020 Firmware: through 3.20
Schneider-Electric Modicon M580 Bmep582020H Firmware: through 3.20
Schneider-Electric Modicon M580 Bmep582040 Firmware: through 3.20
Schneider-Electric Modicon M580 Bmep582040H Firmware: through 3.20
Schneider-Electric Modicon M580 Bmep582040S Firmware: through 3.20
Schneider-Electric Modicon M580 Bmep583020 Firmware: through 3.20
Schneider-Electric Modicon M580 Bmep583040 Firmware: through 3.20
Schneider-Electric Modicon M580 Bmep584020 Firmware: through 3.20
Schneider-Electric Modicon M580 Bmep584040 Firmware: through 3.20

How to fix

Upgrade to a fixed version: Schneider-Electric Modicon M340 Bmxp341000 Firmware 3.40; Schneider-Electric Modicon M340 Bmxp342000 Firmware 3.40; Schneider-Electric Modicon M340 Bmxp3420102 Firmware 3.40; Schneider-Electric Modicon M340 Bmxp342010 Firmware 3.40; Schneider-Electric Modicon M340 Bmxp342020 Firmware 3.40; Schneider-Electric Modicon M340 Bmxp342020H Firmware 3.40; Schneider-Electric Modicon M340 Bmxp3420302 Firmware 3.40; Schneider-Electric Modicon M340 Bmxp3420302H Firmware 3.40; Schneider-Electric Modicon M340 Bmxp342030 Firmware 3.40; Schneider-Electric Modicon M340 Bmxp342030H Firmware 3.40; Schneider-Electric Modicon Mc80 Bmkc8020301 Firmware 1.70; Schneider-Electric Modicon Mc80 Bmkc8020310 Firmware 1.70. Check the vendor advisory for mitigations.

References

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