How severe is CVE-2021-22738?

CVE-2021-22738 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-22738 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-22738?

CVE-2021-22738 primarily affects Schneider-electric Spacelynk Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-22738?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-22738 published?

CVE-2021-22738 was published on 2021-05-26 and last updated on 2026-06-17.

CVE-2021-22738

CVE-2021-22738 is a critical-severity vulnerability in Schneider-electric Spacelynk Firmware with a CVSS 3.x base score of 9.8. 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-327.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 5.0
EPSS exploit prediction: 1% (46th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-327
Affected product: Schneider-electric Spacelynk Firmware
Published: 2021-05-26
Last modified: 2026-06-17

Description

Use of a Broken or Risky Cryptographic Algorithm vulnerability exists in homeLYnk (Wiser For KNX) and spaceLYnk V2.60 and prior that could cause unauthorized access when credentials are discovered after a brute force attack.

Frequently asked questions

What is CVE-2021-22738?: Use of a Broken or Risky Cryptographic Algorithm vulnerability exists in homeLYnk (Wiser For KNX) and spaceLYnk V2.60 and prior that could cause unauthorized access when credentials are discovered after a brute force attack.
How severe is CVE-2021-22738?: CVE-2021-22738 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-22738 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-22738?: CVE-2021-22738 primarily affects Schneider-electric Spacelynk Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-22738?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-22738 published?: CVE-2021-22738 was published on 2021-05-26 and last updated on 2026-06-17.

References

https://download.schneider-electric.com/files?p_Doc_Ref=SEVD-2021-130-04

Affected products (2)

cpe:2.3:o:schneider-electric:spacelynk_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:homelynk_firmware:*:*:*:*:*:*:*:*

More vulnerabilities in Schneider-electric Spacelynk Firmware

CVE-2022-22810 — Critical (CVSS 9.8): A CWE-307: Improper Restriction of Excessive Authentication Attempts vulnerability exists that could allow an attacker…
CVE-2021-22737 — Critical (CVSS 9.8): Insufficiently Protected Credentials vulnerability exists in homeLYnk (Wiser For KNX) and spaceLYnk V2.60 and prior…
CVE-2019-6832 — High (CVSS 8.3): A CWE-287: Authentication vulnerability exists in spaceLYnk (all versions before 2.4.0) and Wiser for KNX (all versions…
CVE-2022-22811 — High (CVSS 8.1): A CWE-352: Cross-Site Request Forgery (CSRF) vulnerability exists that could induce users to perform unintended…
CVE-2021-22733 — High (CVSS 7.8): Improper Privilege Management vulnerability exists in homeLYnk (Wiser For KNX) and spaceLYnk V2.60 and prior which…
CVE-2021-22732 — High (CVSS 7.8): Improper Privilege Management vulnerability exists in homeLYnk (Wiser For KNX) and spaceLYnk V2.60 and prior which…

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