CVE-2020-5140
CVE-2020-5140 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-125.
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-125
- Affected product: Sonicwall Sonicos
- Published:
- Last modified:
Description
A vulnerability in SonicOS allows a remote unauthenticated attacker to cause Denial of Service (DoS) on the firewall SSLVPN service by sending a malicious HTTP request that leads to memory addresses leak. 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-2020-5140?
- A vulnerability in SonicOS allows a remote unauthenticated attacker to cause Denial of Service (DoS) on the firewall SSLVPN service by sending a malicious HTTP request that leads to memory addresses leak. 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-2020-5140?
- CVE-2020-5140 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-2020-5140 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-2020-5140?
- CVE-2020-5140 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-2020-5140?
- 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-2020-5140 published?
- CVE-2020-5140 was published on 2020-10-12 and last updated on 2026-06-17.
References
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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