How severe is CVE-2020-5139?

CVE-2020-5139 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-5139 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-5139?

CVE-2020-5139 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-2020-5139?

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-2020-5139 published?

CVE-2020-5139 was published on 2020-10-12 and last updated on 2026-06-17.

CVE-2020-5139

CVE-2020-5139 is a high-severity vulnerability in Sonicwall Sonicos with a CVSS 3.x base score of 7.5. 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-763.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (75th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-763
Affected product: Sonicwall Sonicos
Published: 2020-10-12
Last modified: 2026-06-17

Description

A vulnerability in SonicOS SSLVPN service allows a remote unauthenticated attacker to cause Denial of Service (DoS) due to the release of Invalid pointer and leads to a firewall crash. 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-2020-5139?: A vulnerability in SonicOS SSLVPN service allows a remote unauthenticated attacker to cause Denial of Service (DoS) due to the release of Invalid pointer and leads to a firewall crash. 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-2020-5139?: CVE-2020-5139 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-5139 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-5139?: CVE-2020-5139 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-2020-5139?: 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-2020-5139 published?: CVE-2020-5139 was published on 2020-10-12 and last updated on 2026-06-17.

References

https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2020-0014

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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