CVE-2025-27587OpenSSL 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…
- 5.3MediumCVSS base score
- 0.47%Exploitation in 30 daysEPSS · top 59% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
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.
Timeline
ID reserved
By mitre
- 4 months later
· 4 months later
Published
- 10 days later
· 10 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N |
| NVDNVD · Deferred | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N |
- EPSS (exploitation in 30 days)
- 0.47% · top 59% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.3.
Affected products
n/a
- affected n/a
References
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2025-18430 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2025-27587)Record last updated .