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: ipv6: mcast: extend RCU protection in igmp6_send() (CVE-2025-21759) * kernel: x86/microcode/AMD: Fix out-of-bounds on systems with CPU-less NUMA nodes (CVE-2025-21991) * kernel: vmxnet3: Fix malformed packet sizing in vmxnet3_process_xdp (CVE-2025-37799) 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
The advisory covers three kernel vulnerabilities: CVE-2025-21759 involves extending RCU protection in the igmp6_send() function related to IPv6 multicast; CVE-2025-21991 fixes an out-of-bounds access on AMD systems with CPU-less NUMA nodes; CVE-2025-37799 addresses malformed packet sizing in the vmxnet3_process_xdp function. These issues affect the Linux kernel core components in Red Hat Enterprise Linux 10 and related variants. The vendor has released updated kernel packages to remediate these vulnerabilities and requires a reboot for the update to take effect.
Potential Impact
The vulnerabilities affect core kernel functionality, potentially leading to memory safety issues (use-after-free, out-of-bounds access) and malformed packet processing. Such flaws can impact system stability, security, and network packet handling. Red Hat rates the overall security impact as Important (high severity). No known exploits in the wild have been reported at this time.
Mitigation Recommendations
Red Hat has released updated kernel packages for Red Hat Enterprise Linux 10 and related variants that address these vulnerabilities. Users should apply the available kernel updates as described in the Red Hat advisory (https://access.redhat.com/articles/11258) and reboot affected systems to ensure the fixes take effect. No additional mitigations are specified beyond applying the official update and rebooting.
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: ipv6: mcast: extend RCU protection in igmp6_send() (CVE-2025-21759) * kernel: x86/microcode/AMD: Fix out-of-bounds on systems with CPU-less NUMA nodes (CVE-2025-21991) * kernel: vmxnet3: Fix malformed packet sizing in vmxnet3_process_xdp (CVE-2025-37799) 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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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The advisory covers three kernel vulnerabilities: CVE-2025-21759 involves extending RCU protection in the igmp6_send() function related to IPv6 multicast; CVE-2025-21991 fixes an out-of-bounds access on AMD systems with CPU-less NUMA nodes; CVE-2025-37799 addresses malformed packet sizing in the vmxnet3_process_xdp function. These issues affect the Linux kernel core components in Red Hat Enterprise Linux 10 and related variants. The vendor has released updated kernel packages to remediate these vulnerabilities and requires a reboot for the update to take effect.
Potential Impact
The vulnerabilities affect core kernel functionality, potentially leading to memory safety issues (use-after-free, out-of-bounds access) and malformed packet processing. Such flaws can impact system stability, security, and network packet handling. Red Hat rates the overall security impact as Important (high severity). No known exploits in the wild have been reported at this time.
Mitigation Recommendations
Red Hat has released updated kernel packages for Red Hat Enterprise Linux 10 and related variants that address these vulnerabilities. Users should apply the available kernel updates as described in the Red Hat advisory (https://access.redhat.com/articles/11258) and reboot affected systems to ensure the fixes take effect. No additional mitigations are specified beyond applying the official update and rebooting.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2025:10371
- Cve Count
- 3
- Additional Cves
- ["CVE-2025-21991","CVE-2025-37799"]
- Cvss Version
- null
Threat ID: 6a3da1e84853345fc182eee5
Added to database: 06/25/2026, 21:47:20 UTC
Last enriched: 06/25/2026, 22:36:53 UTC
Last updated: 07/03/2026, 20:51:22 UTC
Views: 33
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