CVE-2023-2975

Description

Issue summary: The AES-SIV cipher implementation contains a bug that causes it to ignore empty associated data entries which are unauthenticated as a consequence. Impact summary: Applications that use the AES-SIV algorithm and want to authenticate empty data entries as associated data can be misled by removing, adding or reordering such empty entries as these are ignored by the OpenSSL implementation. We are currently unaware of any such applications. The AES-SIV algorithm allows for authentication of multiple associated data entries along with the encryption. To authenticate empty data the application has to call EVP_EncryptUpdate() (or EVP_CipherUpdate()) with NULL pointer as the output buffer and 0 as the input buffer length. The AES-SIV implementation in OpenSSL just returns success for such a call instead of performing the associated data authentication operation. The empty data thus will not be authenticated. As this issue does not affect non-empty associated data authentication and we expect it to be rare for an application to use empty associated data entries this is qualified as Low severity issue.

How to fix CVE-2023-2975

To remediate CVE-2023-2975, upgrade the affected package to a fixed version below.

• —upgrade to 3.0.9-r2 or later
• —upgrade to 3.0.9-r1 or later
• —upgrade to 3.0.10-1~deb12u1 or later

Is CVE-2023-2975 being exploited?

Low — EPSS is 0.2%, meaning exploitation activity has not been observed at scale.

Affected packages (3)

• from 0, < 3.0.9-r2
• from 0, < 3.0.9-r1
• from 0, < 3.0.10-1~deb12u1

CVSS scores

References (2)

• ADVISORYsecurity.alpinelinux.org/vuln/CVE-2023-2975
• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2023-2975