CVE-2025-27587

Public on 2025-06-16
Modified on 2025-06-19
Description
OpenSSL 3.0.0 through 3.3.2 on the PowerPC architecture is vulnerable to a Minerva attack, exploitable by measuring the time of signing of random messages using the EVP_DigestSign API, and then using the private key to extract the K value (nonce) from the signatures. Next, based on the bit size of the extracted nonce, one can compare the signing time of full-sized nonces to signatures that used smaller nonces, via statistical tests. There is a side-channel in the P-364 curve that allows private key extraction (also, there is a dependency between the bit size of K and the size of the side channel). NOTE: This CVE is disputed because the OpenSSL security policy explicitly notes that any side channels which require same physical system to be detected are outside of the threat model for the software. The timing signal is so small that it is infeasible to be detected without having the attacking process running on the same physical system.
Severity
Medium severity
Medium
See what this means
CVSS v3 Base Score
5.1
See breakdown

Affected Packages

Platform Package Release Date Advisory Status
Amazon Linux 2 - Core edk2 Not Affected
Amazon Linux 1 openssl Not Affected
Amazon Linux 2 - Core openssl Not Affected
Amazon Linux 2023 openssl Not Affected
Amazon Linux 2 - Openssl-snapsafe Extra openssl-snapsafe Not Affected
Amazon Linux 2 - Core openssl11 Not Affected

CVSS Scores

Score Type Score Vector
Amazon Linux CVSSv3 5.1 CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
NVD CVSSv3 5.3 CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N