How severe is CVE-2021-22727?

CVE-2021-22727 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-2021-22727 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-22727?

CVE-2021-22727 primarily affects Schneider-electric Evlink City Evc1s22p4 Firmware. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-22727?

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-2021-22727 published?

CVE-2021-22727 was published on 2021-07-21 and last updated on 2026-06-17.

CVE-2021-22727

CVE-2021-22727 is a critical-severity vulnerability in Schneider-electric Evlink City Evc1s22p4 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-331.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-331
Affected product: Schneider-electric Evlink City Evc1s22p4 Firmware
Published: 2021-07-21
Last modified: 2026-06-17

Description

A CWE-331: Insufficient Entropy vulnerability exists in EVlink City (EVC1S22P4 / EVC1S7P4 all versions prior to R8 V3.4.0.1), EVlink Parking (EVW2 / EVF2 / EV.2 all versions prior to R8 V3.4.0.1), and EVlink Smart Wallbox (EVB1A all versions prior to R8 V3.4.0.1 ) that could allow an attacker to gain unauthorized access to the charging station web server

Frequently asked questions

What is CVE-2021-22727?: A CWE-331: Insufficient Entropy vulnerability exists in EVlink City (EVC1S22P4 / EVC1S7P4 all versions prior to R8 V3.4.0.1), EVlink Parking (EVW2 / EVF2 / EV.2 all versions prior to R8 V3.4.0.1), and EVlink Smart Wallbox (EVB1A all versions prior to R8 V3.4.0.1 ) that could allow an attacker to gain unauthorized access to the charging station web server
How severe is CVE-2021-22727?: CVE-2021-22727 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-2021-22727 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-22727?: CVE-2021-22727 primarily affects Schneider-electric Evlink City Evc1s22p4 Firmware. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-22727?: 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-2021-22727 published?: CVE-2021-22727 was published on 2021-07-21 and last updated on 2026-06-17.

References

http://download.schneider-electric.com/files?p_Doc_Ref=SEVD-2021-194-06

Affected products (6)

cpe:2.3:o:schneider-electric:evlink_city_evc1s22p4_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:evlink_city_evc1s7p4_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:evlink_parking_evw2_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:evlink_parking_evf2_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:evlink_parking_ev.2_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:schneider-electric:evlink_smart_wallbox_evb1a_firmware:*:*:*:*:*:*:*:*

More vulnerabilities in Schneider-electric Evlink City Evc1s22p4 Firmware

CVE-2021-22820 — Critical (CVSS 9.8): A CWE-614 Insufficient Session Expiration vulnerability exists that could allow an attacker to maintain an unauthorized…
CVE-2021-22730 — Critical (CVSS 9.8): A CWE-798: Use of Hard-coded Credentials vulnerability exists in EVlink City (EVC1S22P4 / EVC1S7P4 all versions prior…
CVE-2021-22729 — Critical (CVSS 9.8): A CWE-259: Use of Hard-coded Password vulnerability exists in EVlink City (EVC1S22P4 / EVC1S7P4 all versions prior to…
CVE-2021-22707 — Critical (CVSS 9.8): A CWE-798: Use of Hard-coded Credentials vulnerability exists in EVlink City (EVC1S22P4 / EVC1S7P4 all versions prior…
CVE-2021-22821 — High (CVSS 8.6): A CWE-918 Server-Side Request Forgery (SSRF) vulnerability exists that could cause the station web server to forward…
CVE-2021-22726 — High (CVSS 8.1): A CWE-918: Server-Side Request Forgery (SSRF) vulnerability exists in EVlink City (EVC1S22P4 / EVC1S7P4 all versions…

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