CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
NONE
Availability Impact
NONE
AV:N/AC:M/Au:N/C:P/I:N/A:N
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
NONE
Availability Impact
NONE
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS
Percentile
76.8%
OpenVPN, when using a 64-bit block cipher, makes it easier for remote
attackers to obtain cleartext data via a birthday attack against a
long-duration encrypted session, as demonstrated by an HTTP-over-OpenVPN
session using Blowfish in CBC mode, aka a “Sweet32” attack.
Author | Note |
---|---|
mdeslaur | openvpn 2.3 and earlier use BF-CBC by default unless the cipher is specified manually. 2.3.12 was modified to display a warning if a 64-bit cipher is selected. Since this is just a warning, downgrading priority to low |
sbeattie | fixed in 2.4.0 |
CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
NONE
Availability Impact
NONE
AV:N/AC:M/Au:N/C:P/I:N/A:N
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
NONE
Availability Impact
NONE
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS
Percentile
76.8%