How severe is CVE-2020-5143?

CVE-2020-5143 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2020-5143 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-5143?

CVE-2020-5143 primarily affects Sonicwall Sonicos. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-5143?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-5143 published?

CVE-2020-5143 was published on 2020-10-12 and last updated on 2026-06-17.

CVE-2020-5143

CVE-2020-5143 is a medium-severity vulnerability in Sonicwall Sonicos with a CVSS 3.x base score of 5.3. 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-203.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-203
Affected product: Sonicwall Sonicos
Published: 2020-10-12
Last modified: 2026-06-17

Description

SonicOS SSLVPN login page allows a remote unauthenticated attacker to perform firewall management administrator username enumeration based on the server responses. This vulnerability affected SonicOS Gen 5 version 5.9.1.7, 5.9.1.13, Gen 6 version 6.5.4.7, 6.5.1.12, 6.0.5.3, SonicOSv 6.5.4.v and Gen 7 version SonicOS 7.0.0.0.

Frequently asked questions

What is CVE-2020-5143?: SonicOS SSLVPN login page allows a remote unauthenticated attacker to perform firewall management administrator username enumeration based on the server responses. This vulnerability affected SonicOS Gen 5 version 5.9.1.7, 5.9.1.13, Gen 6 version 6.5.4.7, 6.5.1.12, 6.0.5.3, SonicOSv 6.5.4.v and Gen 7 version SonicOS 7.0.0.0.
How severe is CVE-2020-5143?: CVE-2020-5143 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2020-5143 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-5143?: CVE-2020-5143 primarily affects Sonicwall Sonicos. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-5143?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-5143 published?: CVE-2020-5143 was published on 2020-10-12 and last updated on 2026-06-17.

References

https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2020-0018

Affected products (3)

cpe:2.3:o:sonicwall:sonicos:*:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sonicos:7.0.0.0:*:*:*:*:*:*:*
cpe:2.3:o:sonicwall:sonicosv:*:*:*:*:*:*:*:*

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