How severe is CVE-2020-5131?

CVE-2020-5131 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-5131 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-5131?

CVE-2020-5131 affects Sonicwall Netextender. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-5131?

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

When was CVE-2020-5131 published?

CVE-2020-5131 was published on 2020-07-17 and last updated on 2026-06-17.

CVE-2020-5131

CVE-2020-5131 is a high-severity vulnerability in Sonicwall Netextender with a CVSS 3.x base score of 7.8. 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 4.6
EPSS exploit prediction: 1% (42nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Sonicwall Netextender
Published: 2020-07-17
Last modified: 2026-06-17

Description

SonicWall NetExtender Windows client vulnerable to arbitrary file write vulnerability, this allows attacker to overwrite a DLL and execute code with the same privilege in the host operating system. This vulnerability impact SonicWall NetExtender Windows client version 9.0.815 and earlier.

Frequently asked questions

What is CVE-2020-5131?: SonicWall NetExtender Windows client vulnerable to arbitrary file write vulnerability, this allows attacker to overwrite a DLL and execute code with the same privilege in the host operating system. This vulnerability impact SonicWall NetExtender Windows client version 9.0.815 and earlier.
How severe is CVE-2020-5131?: CVE-2020-5131 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-5131 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-5131?: CVE-2020-5131 affects Sonicwall Netextender. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-5131?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-5131 published?: CVE-2020-5131 was published on 2020-07-17 and last updated on 2026-06-17.

References

https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2020-0004

Affected products (1)

cpe:2.3:a:sonicwall:netextender:*:*:*:*:*:windows:*:*

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