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CVE-2021-26318
Side-channels Related to the x86 PREFETCH Instruction
Medium4.7EPSS 0.33%
- Published
- Updated
- Reserved
- Assigned by
- AMD
Description
A timing and power-based side channel attack leveraging the x86 PREFETCH instructions on some AMD CPUs could potentially result in leaked kernel address space information.
Timeline
ID reserved
By AMD
- 9 months later
· 9 months later
Published
- 3 years later
· 3 years 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 |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Medium4.7 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N |
- EPSS (exploitation in 30 days)
- 0.33% · top 74% of all CVEs (7 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.7.
Weakness
Affected products
AMD · All supported processors
- affected unspecified – < undefined
References (1)
- https://www.amd.com/en/corporate/product-security/bulletin/amd-sb-1017 (opens in a new tab)x_refsource_MISCx_transferred
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)
- 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://trackcve.app/cve/CVE-2021-26318)Record last updated .