How severe is CVE-2020-5133?

CVE-2020-5133 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-2020-5133 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-2020-5133?

CVE-2020-5133 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-2020-5133?

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-2020-5133 published?

CVE-2020-5133 was published on 2020-10-12 and last updated on 2026-06-17.

CVE-2020-5133

CVE-2020-5133 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-120.

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-120
Affected product: Sonicwall Sonicos
Published: 2020-10-12
Last modified: 2026-06-17

Description

A vulnerability in SonicOS allows a remote unauthenticated attacker to cause Denial of Service due to buffer overflow, which leads to a firewall crash. This vulnerability affected SonicOS Gen 6 version 6.5.1.12, 6.0.5.3, SonicOSv 6.5.4.v and Gen 7 version 7.0.0.0.

Frequently asked questions

What is CVE-2020-5133?: A vulnerability in SonicOS allows a remote unauthenticated attacker to cause Denial of Service due to buffer overflow, which leads to a firewall crash. This vulnerability affected SonicOS Gen 6 version 6.5.1.12, 6.0.5.3, SonicOSv 6.5.4.v and Gen 7 version 7.0.0.0.
How severe is CVE-2020-5133?: CVE-2020-5133 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-2020-5133 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-2020-5133?: CVE-2020-5133 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-2020-5133?: 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-2020-5133 published?: CVE-2020-5133 was published on 2020-10-12 and last updated on 2026-06-17.

References

https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2020-0008

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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