CVE-2020-20813
CVE-2020-20813 is a high-severity vulnerability in Openvpn 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-400.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- EPSS exploit prediction: 1% (48th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-400
- Affected product: Openvpn
- Published:
- Last modified:
Description
Control Channel in OpenVPN 2.4.7 and earlier allows remote attackers to cause a denial of service via crafted reset packet.
Frequently asked questions
- What is CVE-2020-20813?
- Control Channel in OpenVPN 2.4.7 and earlier allows remote attackers to cause a denial of service via crafted reset packet.
- How severe is CVE-2020-20813?
- CVE-2020-20813 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-2020-20813 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-20813?
- CVE-2020-20813 affects Openvpn. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2020-20813?
- 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-2020-20813 published?
- CVE-2020-20813 was published on 2023-08-22 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:openvpn:openvpn:*:*:*:*:*:*:*:*
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