Skip to main content

Linux Kernel CVE-2025-68313

HIGH
2025-12-16 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Information Disclosure Linux Amd
7.1
CVSS 3.1 · Vendor: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Share

Severity by source

Vendor (416baaa9-dc9f-4396-8d5f-8c081fb06d67) PRIMARY
7.1 HIGH
AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
vuln.today AI
6.3 MEDIUM

Local unprivileged code can call RDSEED (AV:L/PR:L), but impact depends on specific Zen5 microcode and a consumer trusting the value (AC:H); weakened entropy harms confidentiality and integrity, not availability.

3.1 AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
4.0 AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
SUSE
6.1 MEDIUM
AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H
Red Hat
5.5 MEDIUM
qualitative

Primary rating from Vendor (416baaa9-dc9f-4396-8d5f-8c081fb06d67).

CVSS VectorVendor: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None

Lifecycle Timeline

2
Analysis Generated
Jul 30, 2026 - 07:11 vuln.today
CVE Published
Dec 16, 2025 - 16:16 cve.org
HIGH 7.1

DescriptionCVE.org

In the Linux kernel, the following vulnerability has been resolved:

x86/CPU/AMD: Add RDSEED fix for Zen5

There's an issue with RDSEED's 16-bit and 32-bit register output variants on Zen5 which return a random value of 0 "at a rate inconsistent with randomness while incorrectly signaling success (CF=1)". Search the web for AMD-SB-7055 for more detail.

Add a fix glue which checks microcode revisions.

[ bp: Add microcode revisions checking, rewrite. ]

AnalysisAI

Weakened cryptographic randomness affects the Linux kernel on AMD Zen5 processors, where the RDSEED instruction's 16-bit and 32-bit register variants can return a zero value while falsely reporting success (CF=1), tracked upstream as AMD-SB-7055. Kernel and userspace consumers that rely on RDSEED for entropy can silently receive predictable seed material, undermining key generation and other cryptographic operations. There is no public exploit identified at time of analysis and EPSS is low (0.16%, 6th percentile); the kernel resolves this by adding a microcode-revision check that works around the faulty hardware behavior.

Technical ContextAI

RDSEED is an x86 hardware instruction that draws from the CPU's on-die true random number generator (DRBG/entropy source) and sets the carry flag (CF=1) to signal that a valid random value was returned. On affected AMD Zen5 CPUs a hardware defect causes the 16-bit and 32-bit output forms of RDSEED to occasionally return 0 while still setting CF=1, so software cannot distinguish a genuine random result from a failed one. Because the Linux kernel and libraries feed RDSEED output into entropy pools and cryptographic seeding, the defect propagates weak or predictable randomness upward. No CWE was assigned in the input, but the root-cause class is best described as use of insufficiently random / predictable values arising from an improper hardware failure signal; the kernel fix (commits authored/reworked by Borislav Petkov) gates the workaround on specific microcode revisions rather than blanket-disabling the instruction.

Affected ProductsAI

The affected product is the Linux kernel running on AMD Zen5 (Family 1Ah) processors with vulnerable microcode revisions; the flaw originates in the CPU hardware (AMD-SB-7055) and is mitigated in the kernel's x86/CPU/AMD code. No specific fixed kernel tag is stated in the input, but the fix is present in the mainline/stable tree via commits 36ff93e66d0efc46e39fab536a9feec968daa766, 607b9fb2ce248cc5b633c5949e0153838992c152, and e980de2ff109dacb6d9d3a77f01b27c467115ecb (git.kernel.org stable references). No vendor CPE string was provided in the input, and exact affected/fixed kernel version numbers are not enumerated in the supplied data.

RemediationAI

Upstream fix available (PR/commit); released patched version not independently confirmed - apply a kernel build that includes the stable commits 36ff93e6, 607b9fb2, and e980de2f (https://git.kernel.org/stable/c/36ff93e66d0efc46e39fab536a9feec968daa766, https://git.kernel.org/stable/c/607b9fb2ce248cc5b633c5949e0153838992c152, https://git.kernel.org/stable/c/e980de2ff109dacb6d9d3a77f01b27c467115ecb), which add the microcode-revision-gated RDSEED workaround. In parallel, apply the AMD microcode update referenced by AMD-SB-7055, since the defect is ultimately in CPU firmware and updated microcode is the authoritative fix. As a compensating control where the kernel/microcode cannot yet be updated, avoid depending on RDSEED as a sole entropy source: ensure the kernel RNG blends multiple entropy inputs (jitter entropy, hardware TPM/RNG, prior seed) so a zeroed RDSEED result cannot dominate seeding - the trade-off is slightly slower entropy availability at boot. Prefer regenerating any long-lived cryptographic keys that may have been produced on affected Zen5 systems before patching, since predictable seed material may have weakened them.

More in Amd

View all
CVE-2021-22986 CRITICAL POC
9.8 Mar 31

On BIG-IP versions 16.0.x before 16.0.1.1, 15.1.x before 15.1.2.1, 14.1.x before 14.1.4, 13.1.x before 13.1.3.6, and 12.
CVE-2020-6103 CRITICAL POC
9.9 Jul 20

An exploitable code execution vulnerability exists in the Shader functionality of AMD Radeon DirectX 11 Driver atidxx64.
CVE-2020-6102 CRITICAL POC
9.9 Jul 20

An exploitable code execution vulnerability exists in the Shader functionality of AMD Radeon DirectX 11 Driver atidxx64.
CVE-2020-6101 CRITICAL POC
9.9 Jul 20

An exploitable code execution vulnerability exists in the Shader functionality of AMD Radeon DirectX 11 Driver atidxx64.
CVE-2020-6100 CRITICAL POC
9.9 Jul 20

An exploitable memory corruption vulnerability exists in AMD atidxx64.dll 26.20.15019.19000 graphics driver. Rated criti
CVE-2018-6546 CRITICAL POC
9.8 Apr 13

plays_service.exe in the plays.tv service before 1.27.7.0, as distributed in AMD driver-installation packages and Gaming
CVE-2021-3653 HIGH POC
8.8 Sep 29

A flaw was found in the KVM's AMD code for supporting SVM nested virtualization. Rated high severity (CVSS 8.8), this vu
CVE-2020-12138 HIGH POC
8.8 Apr 27

AMD ATI atillk64.sys 5.11.9.0 allows low-privileged users to interact directly with physical memory by calling one of se
CVE-2019-5098 HIGH POC
8.6 Dec 05

An exploitable out-of-bounds read vulnerability exists in AMD ATIDXX64.DLL driver, version 26.20.13001.29010. Rated high
CVE-2015-7724 HIGH POC
7.8 Jun 07

AMD fglrx-driver before 15.9 allows local users to gain privileges via a symlink attack. Rated high severity (CVSS 7.8),
CVE-2015-7723 HIGH POC
7.8 Jun 07

AMD fglrx-driver before 15.7 allows local users to gain privileges via a symlink attack. Rated high severity (CVSS 7.8),
CVE-2023-1048 HIGH POC
7.8 Feb 26

A vulnerability, which was classified as critical, has been found in TechPowerUp Ryzen DRAM Calculator 1.2.0.5.sys. Rate

Same technique Information Disclosure

View all
CVE-2019-2725 CRITICAL POC
9.8
CVE-2021-34523 CRITICAL POC
9.0
CVE-2013-2251 CRITICAL POC
9.8
CVE-2017-5638 CRITICAL POC
9.8
CVE-2025-24813 CRITICAL POC
9.8
CVE-2015-1701 HIGH POC
7.8
CVE-2017-0147 HIGH POC
7.5
CVE-2014-6324 HIGH POC
8.8

Vendor StatusVendor

SUSE

Severity: Moderate
Product Status
Container suse/sl-micro/6.0/baremetal-os-container:latest Affected
Container suse/sl-micro/6.0/base-os-container:2.1.3-7.95 Image SL-Micro Affected
Container suse/sl-micro/6.0/kvm-os-container:2.1.3-6.115 Affected
Container suse/sl-micro/6.0/rt-os-container:2.1.3-7.146 Affected
Container suse/sl-micro/6.0/toolbox:latest Affected

Share

CVE-2025-68313 vulnerability details – vuln.today
Back

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy