CVE-2025-22866

Secret-scalar bit disclosure via variable-time branch

Published Feb 6, 2025 · Updated Feb 21, 2025

Observable timing discrepancy in Go's crypto/internal/nistec on ppc64le allows local users to infer bits of P-256 secret scalars. The p256NegCond assembly routine branches on a secret-dependent condition instead of using a constant-time conditional move, causing execution time to vary with scalar data. The leak is limited to ppc64le, and Go reports that it is insufficient to recover a P-256 private key in known protocols.

CVSS severity4.0
Medium
EPSS probability0.29%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Observable timing discrepancy in Go's crypto/internal/nistec on ppc64le allows local users to infer bits of P-256 secret scalars. The p256NegCond assembly routine branches on a secret-dependent condition instead of using a constant-time conditional move, causing execution time to vary with scalar data. The leak is limited to ppc64le, and Go reports that it is insufficient to recover a P-256 private key in known protocols.

The record

CVE
CVE-2025-22866
Published
Feb 6, 2025
Updated
Feb 21, 2025
Vendor
Go standard library
Product
crypto/internal/nistec
Classifications
CWE-208
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 6, 2025CVE publishedPublication date reported by the CVE source.
  2. Feb 21, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <1.22.12
  2. Affected versionversion=1.23.0-0 <1.23.6
  3. Affected versionversion=1.24.0-0 <1.24.0-rc.3

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Go standard library · crypto/internal/nistecversion=0 <1.22.12; version=1.23.0-0 <1.23.6; version=1.24.0-0 <1.24.0-rc.3

Published CVSS scores

4.0CISA-ADPCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-208Observable Timing Discrepancy

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo