No exploitation reportedFix available

CVE-2021-22731

Q: Is CVE-2021-22731 actively exploited?

Active exploitation of CVE-2021-22731 has not been confirmed. Its EPSS score was 1.4% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-2021-22731?

CVE-2021-22731 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

No exploitation reported by the sources we read.

Published2021-05-26
Fixed in8.22
WeaknessCWE-640

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

Weak Password Recovery Mechanism for Forgotten Password vulnerability exists on Modicon Managed Switch MCSESM* and MCSESP* V8.21 and prior which could cause an unauthorized password change through HTTP / HTTPS when basic user information is known by a remote attacker.

Timeline

dates in UTC

2021-05-2620:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 18:48 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-22731?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-22731?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD

Schneider-electric mcsesm043f23f0 firmwareversion to verify

Branch	Affected	Fixed in	Source
8.22	< 8.22	8.22	NVD

Schneider-electric mcsesm053f1cs0 firmwareversion to verify

Branch	Affected	Fixed in	Source
8.22	< 8.22	8.22	NVD

Schneider-electric mcsesm053f1cu0 firmwareversion to verify

Branch	Affected	Fixed in	Source
8.22	< 8.22	8.22	NVD

13 more products in the sources.

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Update Schneider-electric mcsesm043f23f0 firmware to 8.22

Advisories and patches

download.schneider-electric.comPatch · Vendor Advisory

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

NVDCVSS 3.19.8read 2026-10-23
NVDCVSS 2.07.5read 2026-10-23
CNAweakness (CWE)CWE-640read 2026-10-23
FIRST EPSSEPSS score1.4 %2026-10-22

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published: 2021-05-26
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2021-22731?

Is CVE-2021-22731 actively exploited?

Active exploitation of CVE-2021-22731 has not been confirmed. Its EPSS score was 1.4% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-22731?

CVE-2021-22731 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

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