What’s Vulnerable › Vulnerabilities

CVE-2026-31628: x86/CPU: Fix FPDSS on Zen1

• Severity: medium (CVSS 5.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.1% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-04-24 · updated 2026-10-15

Description

In the Linux kernel, the following vulnerability has been resolved: x86/CPU: Fix FPDSS on Zen1 Zen1's hardware divider can leave, under certain circumstances, partial results from previous operations. Those results can be leaked by another, attacker thread. Fix that with a chicken bit.

Affected products

• Linux kernel: from 3.16.58 before 3.17; from 4.4.144 before 4.5; from 4.9.102 before 4.10; from 4.14.1 before 5.10.253; from 5.11 before 5.15.203; from 5.16 before 6.1.169 — fixed in 3.17, 4.10, 4.5, 5.10.253, 5.15.203, 6.1.169

How to fix

Upgrade to a fixed version: Linux kernel 3.17, 4.10, 4.5, 5.10.253. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/0548529af20e68c6552817834b766646dd3bd7a7
• https://git.kernel.org/stable/c/1272cfedf4cd1019ddf583917a99b62f2d3645bb
• https://git.kernel.org/stable/c/546785c719418c6166834a47e372a88f5f7ae893
• https://git.kernel.org/stable/c/91f02726b2203b71545713ecb7fb006e60a2d66f
• https://git.kernel.org/stable/c/ad17f07e95e6e8505e2153e5b391f0d27eacce25
• https://git.kernel.org/stable/c/b731aca06387b195058a9f6449a03b62efa1bd10
• https://git.kernel.org/stable/c/e55d98e7756135f32150b9b8f75d580d0d4b2dd3
• https://git.kernel.org/stable/c/e6af5286efe5a56128b34032572c9ce9ebeccda3
• https://git.kernel.org/stable/c/ed7a3a246309ccc807238f1b4f159ee6d37ff9c4
• https://cert-portal.siemens.com/productcert/html/ssa-019113.html
• https://cert-portal.siemens.com/productcert/html/ssa-082556.html
• https://cert-portal.siemens.com/productcert/html/ssa-457936.html

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