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: NFS: Fix filehandle bounds checking in nfs_fh_to_dentry() (CVE-2025-39730) * kernel: tcp: Clear tcp_sk(sk)->fastopen_rsk in tcp_disconnect() (CVE-2025-39955) 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
This advisory addresses two vulnerabilities in the Linux kernel packages distributed by Red Hat. CVE-2025-39730 involves a bounds checking flaw in the nfs_fh_to_dentry() function related to NFS filehandle processing, which could lead to improper memory access. CVE-2025-39955 involves clearing the tcp_sk(sk)->fastopen_rsk pointer in tcp_disconnect() to avoid stale references. Both issues are fixed in the updated kernel packages for Red Hat Enterprise Linux 10. The advisory does not provide CVSS scores but classifies the impact as moderate. The update requires a system reboot to apply the kernel changes.
Potential Impact
The vulnerabilities could potentially allow improper memory handling in the kernel's NFS filehandle processing and TCP socket management, which may lead to system instability or other unintended behavior. Red Hat 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 these vulnerabilities. Users should apply the kernel update for Red Hat Enterprise Linux 10 as described in the advisory and reboot their systems to activate the fixes. Refer to Red Hat's official update instructions at https://access.redhat.com/articles/11258 for detailed guidance.
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: NFS: Fix filehandle bounds checking in nfs_fh_to_dentry() (CVE-2025-39730) * kernel: tcp: Clear tcp_sk(sk)->fastopen_rsk in tcp_disconnect() (CVE-2025-39955) 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
This advisory addresses two vulnerabilities in the Linux kernel packages distributed by Red Hat. CVE-2025-39730 involves a bounds checking flaw in the nfs_fh_to_dentry() function related to NFS filehandle processing, which could lead to improper memory access. CVE-2025-39955 involves clearing the tcp_sk(sk)->fastopen_rsk pointer in tcp_disconnect() to avoid stale references. Both issues are fixed in the updated kernel packages for Red Hat Enterprise Linux 10. The advisory does not provide CVSS scores but classifies the impact as moderate. The update requires a system reboot to apply the kernel changes.
Potential Impact
The vulnerabilities could potentially allow improper memory handling in the kernel's NFS filehandle processing and TCP socket management, which may lead to system instability or other unintended behavior. Red Hat 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 these vulnerabilities. Users should apply the kernel update for Red Hat Enterprise Linux 10 as described in the advisory and reboot their systems to activate the fixes. Refer to Red Hat's official update instructions at https://access.redhat.com/articles/11258 for detailed guidance.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2025:21931
- Cve Count
- 2
- Additional Cves
- ["CVE-2025-39955"]
- Cvss Version
- null
Threat ID: 6a3da1db4853345fc18291ac
Added to database: 06/25/2026, 21:47:07 UTC
Last enriched: 06/25/2026, 22:20:54 UTC
Last updated: 07/02/2026, 22:23:22 UTC
Views: 8
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