Red Hat Security Advisory: kernel security update
The kernel packages contain the Linux kernel, the core of any Linux operating system. Security Fix(es): * kernel: x86/microcode/AMD: Fix out-of-bounds on systems with CPU-less NUMA nodes (CVE-2025-21991) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
AI Analysis
Technical Summary
CVE-2025-21991 is an out-of-bounds memory access vulnerability in the Linux kernel's x86/microcode/AMD component affecting systems with CPU-less NUMA nodes. This vulnerability is classified under CWE-787 (Out-of-bounds Write). Red Hat has issued a security advisory (RHSA-2025:10837) providing updated kernel packages for Red Hat Enterprise Linux 9 and related variants to fix this issue. The advisory rates the impact as moderate and requires a system reboot after patch installation. No CVSS score is provided in the advisory.
Potential Impact
The vulnerability could lead to memory corruption due to out-of-bounds access on affected systems, potentially causing system instability or other unintended behavior. The advisory rates the security impact as moderate. There are no known exploits in the wild at this time.
Mitigation Recommendations
Red Hat has released updated kernel packages that fix this vulnerability. Users should apply the kernel update as described in the Red Hat advisory RHSA-2025:10837 and reboot their systems to ensure the patch takes effect. Patch status is confirmed by the vendor advisory. No additional mitigation steps are specified.
Red Hat Security Advisory: kernel security update
Description
The kernel packages contain the Linux kernel, the core of any Linux operating system. Security Fix(es): * kernel: x86/microcode/AMD: Fix out-of-bounds on systems with CPU-less NUMA nodes (CVE-2025-21991) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2025-21991 is an out-of-bounds memory access vulnerability in the Linux kernel's x86/microcode/AMD component affecting systems with CPU-less NUMA nodes. This vulnerability is classified under CWE-787 (Out-of-bounds Write). Red Hat has issued a security advisory (RHSA-2025:10837) providing updated kernel packages for Red Hat Enterprise Linux 9 and related variants to fix this issue. The advisory rates the impact as moderate and requires a system reboot after patch installation. No CVSS score is provided in the advisory.
Potential Impact
The vulnerability could lead to memory corruption due to out-of-bounds access on affected systems, potentially causing system instability or other unintended behavior. The advisory rates the security impact as moderate. There are no known exploits in the wild at this time.
Mitigation Recommendations
Red Hat has released updated kernel packages that fix this vulnerability. Users should apply the kernel update as described in the Red Hat advisory RHSA-2025:10837 and reboot their systems to ensure the patch takes effect. Patch status is confirmed by the vendor advisory. No additional mitigation steps are specified.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2025:10837
- Cve Count
- 1
- Additional Cves
- []
- Cvss Version
- null
Threat ID: 6a3da1e84853345fc182ed36
Added to database: 06/25/2026, 21:47:20 UTC
Last enriched: 06/25/2026, 22:35:53 UTC
Last updated: 07/02/2026, 01:17:52 UTC
Views: 7
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