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: NFSD: fix hang in nfsd4_shutdown_callback (CVE-2025-21795) * kernel: KVM: arm64: Tear down vGIC on failed vCPU creation (CVE-2025-37849) * kernel: Linux kernel: ALSA: ump buffer overflow via malformed UMP SysEx message (CVE-2025-37891) * kernel: NFS: Fix a race when updating an existing write (CVE-2025-39697) * kernel: ASoC: Intel: bytcr_rt5640: Fix invalid quirk input mapping (CVE-2025-40154) * kernel: libceph: fix potential use-after-free in have_mon_and_osd_map() (CVE-2025-68285) 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 Red Hat security advisory (RHSA-2026:0804) addresses six distinct vulnerabilities in the Linux kernel packages for Red Hat Enterprise Linux 9.6 Extended Update Support. The fixed issues include: a hang in nfsd4_shutdown_callback (CVE-2025-21795), teardown of vGIC on failed vCPU creation in KVM arm64 (CVE-2025-37849), a buffer overflow in ALSA via malformed UMP SysEx messages (CVE-2025-37891), a race condition when updating an existing NFS write (CVE-2025-39697), an invalid quirk input mapping in Intel bytcr_rt5640 ASoC driver (CVE-2025-40154), and a potential use-after-free in libceph (CVE-2025-68285). Red Hat has released updated kernel packages that fix these vulnerabilities and requires a system reboot for the update to take effect.
Potential Impact
The vulnerabilities collectively affect the Linux kernel core components and drivers, potentially causing system hangs, memory corruption, race conditions, and use-after-free scenarios. These issues could impact system stability and security on affected Red Hat Enterprise Linux 9.6 systems. The advisory rates the overall security impact as Important (high severity). There are no known exploits in the wild at the time of this advisory.
Mitigation Recommendations
Red Hat has released updated kernel packages that address these vulnerabilities. Users of Red Hat Enterprise Linux 9.6 Extended Update Support should apply the provided kernel update and reboot their systems to ensure the fixes take effect. For detailed update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigations are indicated by the vendor advisory.
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: NFSD: fix hang in nfsd4_shutdown_callback (CVE-2025-21795) * kernel: KVM: arm64: Tear down vGIC on failed vCPU creation (CVE-2025-37849) * kernel: Linux kernel: ALSA: ump buffer overflow via malformed UMP SysEx message (CVE-2025-37891) * kernel: NFS: Fix a race when updating an existing write (CVE-2025-39697) * kernel: ASoC: Intel: bytcr_rt5640: Fix invalid quirk input mapping (CVE-2025-40154) * kernel: libceph: fix potential use-after-free in have_mon_and_osd_map() (CVE-2025-68285) 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 Red Hat security advisory (RHSA-2026:0804) addresses six distinct vulnerabilities in the Linux kernel packages for Red Hat Enterprise Linux 9.6 Extended Update Support. The fixed issues include: a hang in nfsd4_shutdown_callback (CVE-2025-21795), teardown of vGIC on failed vCPU creation in KVM arm64 (CVE-2025-37849), a buffer overflow in ALSA via malformed UMP SysEx messages (CVE-2025-37891), a race condition when updating an existing NFS write (CVE-2025-39697), an invalid quirk input mapping in Intel bytcr_rt5640 ASoC driver (CVE-2025-40154), and a potential use-after-free in libceph (CVE-2025-68285). Red Hat has released updated kernel packages that fix these vulnerabilities and requires a system reboot for the update to take effect.
Potential Impact
The vulnerabilities collectively affect the Linux kernel core components and drivers, potentially causing system hangs, memory corruption, race conditions, and use-after-free scenarios. These issues could impact system stability and security on affected Red Hat Enterprise Linux 9.6 systems. The advisory rates the overall security impact as Important (high severity). There are no known exploits in the wild at the time of this advisory.
Mitigation Recommendations
Red Hat has released updated kernel packages that address these vulnerabilities. Users of Red Hat Enterprise Linux 9.6 Extended Update Support should apply the provided kernel update and reboot their systems to ensure the fixes take effect. For detailed update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigations are indicated by the vendor advisory.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:0804
- Cve Count
- 6
- Additional Cves
- ["CVE-2025-37849","CVE-2025-37891","CVE-2025-39697","CVE-2025-40154","CVE-2025-68285"]
- Cvss Version
- null
Threat ID: 6a3da1ca4853345fc1821f9f
Added to database: 06/25/2026, 21:46:50 UTC
Last enriched: 06/25/2026, 22:02:13 UTC
Last updated: 07/02/2026, 20:51:15 UTC
Views: 11
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