High severity · published Jul 12, 2021
CVE-2021-3547
OpenVPN 3 Core Library version 3.6 and 3.6.1 allows a man-in-the-middle attacker to bypass the certificate authentication by issuing an unrelated server certificate using the same…
7.4
CVSS
1.2%
EPSS
No
On KEV
Description
OpenVPN 3 Core Library version 3.6 and 3.6.1 allows a man-in-the-middle attacker to bypass the certificate authentication by issuing an unrelated server certificate using the same hostname found in the verify-x509-name option in a client configuration.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.2% · higher than 69% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OP
Openvpn · Openvpn
3.6; 3.6.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-3547
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-3547
Patch
https://community.openvpn.net/openvpn/wiki/CVE-2021-3547
Vendor Advisory
https://community.openvpn.net/openvpn/wiki/SecurityAnnouncements
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