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: rtmutex: Use waiter::task instead of current in remove_waiter() (CVE-2026-43499) * kernel: futex/requeue: Prevent NULL pointer dereference in remove_waiter() on self-deadlock (CVE-2026-53166) * kernel: xfs: resample the data fork mapping after cycling ILOCK 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 covers multiple kernel vulnerabilities fixed in Red Hat Enterprise Linux 8.4. CVE-2026-43499 addresses an issue in the rtmutex code where waiter::task is now used instead of current in remove_waiter(), preventing potential misuse. CVE-2026-53166 fixes a NULL pointer dereference in futex/requeue during self-deadlock conditions. Additionally, a kernel flaw causing XFS filesystem data corruption when using reflink has been corrected. These vulnerabilities have a CVSS 3.1 base score indicating high severity with impacts on confidentiality, integrity, and availability. The vendor advisory confirms that updated kernel packages are available and that a reboot is required to apply the fixes.
Potential Impact
The vulnerabilities allow for potential privilege escalation or denial of service due to kernel memory corruption or NULL pointer dereference. The XFS data corruption issue could lead to loss or corruption of filesystem data. The CVSS vector indicates local attack vector with low complexity and no user interaction required, resulting in high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
Red Hat has released updated kernel packages for Red Hat Enterprise Linux 8.4 that address these vulnerabilities. Users should apply the security update as described in the Red Hat advisory RHSA-2026:39984 and reboot affected systems to ensure the fixes take effect. No additional mitigations are specified beyond applying the official update.
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: rtmutex: Use waiter::task instead of current in remove_waiter() (CVE-2026-43499) * kernel: futex/requeue: Prevent NULL pointer dereference in remove_waiter() on self-deadlock (CVE-2026-53166) * kernel: xfs: resample the data fork mapping after cycling ILOCK 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.
CVSS v3.1
Score 7.8high
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This advisory covers multiple kernel vulnerabilities fixed in Red Hat Enterprise Linux 8.4. CVE-2026-43499 addresses an issue in the rtmutex code where waiter::task is now used instead of current in remove_waiter(), preventing potential misuse. CVE-2026-53166 fixes a NULL pointer dereference in futex/requeue during self-deadlock conditions. Additionally, a kernel flaw causing XFS filesystem data corruption when using reflink has been corrected. These vulnerabilities have a CVSS 3.1 base score indicating high severity with impacts on confidentiality, integrity, and availability. The vendor advisory confirms that updated kernel packages are available and that a reboot is required to apply the fixes.
Potential Impact
The vulnerabilities allow for potential privilege escalation or denial of service due to kernel memory corruption or NULL pointer dereference. The XFS data corruption issue could lead to loss or corruption of filesystem data. The CVSS vector indicates local attack vector with low complexity and no user interaction required, resulting in high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
Red Hat has released updated kernel packages for Red Hat Enterprise Linux 8.4 that address these vulnerabilities. Users should apply the security update as described in the Red Hat advisory RHSA-2026:39984 and reboot affected systems to ensure the fixes take effect. No additional mitigations are specified beyond applying the official update.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-cqc6-9f34-295v
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-43499"]
- Ecosystems
- []
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
Threat ID: 6a4f6c2c68715ace43158095
Added to database: 07/09/2026, 09:38:52 UTC
Last enriched: 07/26/2026, 01:56:27 UTC
Last updated: 08/25/2026, 10:52:09 UTC
Views: 76
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