OpenVPN up to 2.4.7 Control Channel denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.8$0-$5k0.00

Summaryinfo

A vulnerability was found in OpenVPN up to 2.4.7. It has been declared as problematic. This vulnerability affects unknown code of the component Control Channel. The manipulation results in denial of service. This vulnerability was named CVE-2020-20813. The attack may be performed from remote. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in OpenVPN up to 2.4.7 (Network Encryption Software). It has been classified as problematic. Affected is some unknown processing of the component Control Channel. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on availability. CVE summarizes:

Control Channel in OpenVPN 2.4.7 and earlier allows remote attackers to cause a denial of service via crafted reset packet.

The weakness was presented 08/23/2023. The advisory is shared for download at freebuf.com. This vulnerability is traded as CVE-2020-20813 since 08/13/2020. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1499.

Upgrading to version 2.4.8 eliminates this vulnerability.

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Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.9
VulDB Meta Temp Score: 5.8

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: OpenVPN 2.4.8

Timelineinfo

08/13/2020 🔍
08/23/2023 +1105 days 🔍
08/23/2023 +0 days 🔍
02/03/2026 +895 days 🔍

Sourcesinfo

Advisory: freebuf.com
Status: Confirmed

CVE: CVE-2020-20813 (🔍)
GCVE (CVE): GCVE-0-2020-20813
GCVE (VulDB): GCVE-100-237768

Entryinfo

Created: 08/23/2023 10:11
Updated: 02/03/2026 14:41
Changes: 08/23/2023 10:11 (38), 09/16/2023 07:31 (11), 10/07/2024 22:13 (16), 02/03/2026 14:38 (2), 02/03/2026 14:41 (6)
Complete: 🔍
Committer: lywand
Cache ID: 216::103

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