CVE-2025-27587

Publication date 16 June 2025

Last updated 13 January 2026

Ubuntu priority

Low

Why this priority?

Cvss 3 Severity Score

5.3 · Medium

Score breakdown

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.

Read the notes from the security team

Why is this CVE low priority?

Not considered a security issue by OpenSSL developers

Learn more about Ubuntu priority

Status

Package Ubuntu Release Status
openssl1.0 25.10 questing Not in release
25.04 plucky Not in release
24.10 oracular Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
18.04 LTS bionic
Not affected
nodejs 25.10 questing
Not affected
25.04 plucky
Not affected
24.10 oracular
Not affected
24.04 LTS noble
Not affected
22.04 LTS jammy Ignored disputed by OpenSSL develpers
20.04 LTS focal
Not affected
18.04 LTS bionic Ignored disputed by OpenSSL develpers
16.04 LTS xenial Ignored disputed by OpenSSL develpers
14.04 LTS trusty
Not affected
edk2 25.10 questing
Not affected
25.04 plucky
Not affected
24.10 oracular Ignored end of life, was needs-triage
24.04 LTS noble
Not affected
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
openssl 25.10 questing
Not affected
25.04 plucky
Not affected
24.10 oracular Ignored end of life, was needs-triage
24.04 LTS noble Ignored disputed by OpenSSL develpers
22.04 LTS jammy   Ignored disputed by OpenSSL develpers
20.04 LTS focal  
Not affected
18.04 LTS bionic  
Not affected
16.04 LTS xenial  
Not affected
14.04 LTS trusty
Not affected

Notes

mdeslaur

OpenSSL developers don't consider this to be a security issue within their threat model, see: https://github.com/openssl/openssl/issues/24253#issuecomment-2144391562

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
openssl

Severity score breakdown

Parameter Value
Base score 5.3 · Medium
Attack vector Network
Attack complexity High
Privileges required Low
User interaction None
Scope Unchanged
Confidentiality High
Integrity impact None
Availability impact None
Vector CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N

References

Other references