5.9 Medium
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:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
0.002 Low
EPSS
Percentile
52.4%
A timing based side channel exists in the OpenSSL RSA Decryption
implementation which could be sufficient to recover a plaintext across a
network in a Bleichenbacher style attack. To achieve a successful
decryption an attacker would have to be able to send a very large number of
trial messages for decryption. The vulnerability affects all RSA padding
modes: PKCS#1 v1.5, RSA-OEAP and RSASVE. For example, in a TLS connection,
RSA is commonly used by a client to send an encrypted pre-master secret to
the server. An attacker that had observed a genuine connection between a
client and a server could use this flaw to send trial messages to the
server and record the time taken to process them. After a sufficiently
large number of messages the attacker could recover the pre-master secret
used for the original connection and thus be able to decrypt the
application data sent over that connection.
Author | Note |
---|---|
mdeslaur | Due to the substantial code changes required to fix this side channel issue and others like it in the 1.0.2 and earlier codebases, we will not be fixing this issue in bionic and earlier to not introduce possible regressions. The commit was later reverted, and a more simplified fix was used, see: https://git.openssl.org/gitweb/?p=openssl.git;a=commit;h=0372649a943fb23f7f08c7acdbc01464b9df03f0 https://git.openssl.org/gitweb/?p=openssl.git;a=commit;h=3f499b24f3bcd66db022074f7e8b4f6ee266a3ae |
OS | Version | Architecture | Package | Version | Filename |
---|---|---|---|---|---|
ubuntu | 18.04 | noarch | edk2 | < any | UNKNOWN |
ubuntu | 20.04 | noarch | edk2 | < any | UNKNOWN |
ubuntu | 22.04 | noarch | edk2 | < any | UNKNOWN |
ubuntu | 16.04 | noarch | edk2 | < any | UNKNOWN |
ubuntu | 22.04 | noarch | nodejs | < 12.22.9~dfsg-1ubuntu3.3 | UNKNOWN |
ubuntu | 18.04 | noarch | openssl | < 1.1.1-1ubuntu2.1~18.04.21 | UNKNOWN |
ubuntu | 20.04 | noarch | openssl | < 1.1.1f-1ubuntu2.17 | UNKNOWN |
ubuntu | 22.04 | noarch | openssl | < 3.0.2-0ubuntu1.8 | UNKNOWN |
ubuntu | 22.10 | noarch | openssl | < 3.0.5-2ubuntu2.1 | UNKNOWN |
ubuntu | 23.04 | noarch | openssl | < 3.0.8-1ubuntu1 | UNKNOWN |