Red Hat Security Advisory: kernel-rt security update
The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements. Security Fix(es): * kernel: media: rc: fix races with imon_disconnect() (CVE-2025-39993) * kernel: sctp: avoid NULL dereference when chunk data buffer is missing (CVE-2025-40240) * 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 advisory covers three security fixes in the Red Hat kernel-rt packages: CVE-2025-39993 addresses race conditions in the media rc subsystem related to imon_disconnect(); CVE-2025-40240 fixes a NULL pointer dereference in SCTP when chunk data buffers are missing; and CVE-2025-68285 resolves a potential use-after-free vulnerability in the libceph function have_mon_and_osd_map(). These vulnerabilities affect the Real Time Linux Kernel used in Red Hat Enterprise Linux 8 variants. The update is rated as important and requires a reboot after installation. No CVSS scores are provided in the advisory, but the severity is assessed as high based on the nature of the flaws and Red Hat's rating.
Potential Impact
Successful exploitation of these vulnerabilities could lead to system instability or crashes due to race conditions, NULL pointer dereferences, or use-after-free bugs in kernel components. This may affect system reliability and could potentially be leveraged for denial of service or other impacts depending on the environment. The advisory does not report known exploits in the wild.
Mitigation Recommendations
Red Hat has released an official security update for the kernel-rt packages addressing these vulnerabilities. Users should apply the update as described in the Red Hat advisory RHSA-2026:0443 and reboot the system to ensure the fixes take effect. No additional mitigations are specified or required beyond applying the official patch.
Red Hat Security Advisory: kernel-rt security update
Description
The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements. Security Fix(es): * kernel: media: rc: fix races with imon_disconnect() (CVE-2025-39993) * kernel: sctp: avoid NULL dereference when chunk data buffer is missing (CVE-2025-40240) * 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
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This advisory covers three security fixes in the Red Hat kernel-rt packages: CVE-2025-39993 addresses race conditions in the media rc subsystem related to imon_disconnect(); CVE-2025-40240 fixes a NULL pointer dereference in SCTP when chunk data buffers are missing; and CVE-2025-68285 resolves a potential use-after-free vulnerability in the libceph function have_mon_and_osd_map(). These vulnerabilities affect the Real Time Linux Kernel used in Red Hat Enterprise Linux 8 variants. The update is rated as important and requires a reboot after installation. No CVSS scores are provided in the advisory, but the severity is assessed as high based on the nature of the flaws and Red Hat's rating.
Potential Impact
Successful exploitation of these vulnerabilities could lead to system instability or crashes due to race conditions, NULL pointer dereferences, or use-after-free bugs in kernel components. This may affect system reliability and could potentially be leveraged for denial of service or other impacts depending on the environment. The advisory does not report known exploits in the wild.
Mitigation Recommendations
Red Hat has released an official security update for the kernel-rt packages addressing these vulnerabilities. Users should apply the update as described in the Red Hat advisory RHSA-2026:0443 and reboot the system to ensure the fixes take effect. No additional mitigations are specified or required beyond applying the official patch.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:0443
- Cve Count
- 3
- Additional Cves
- ["CVE-2025-40240","CVE-2025-68285"]
- Cvss Version
- null
Threat ID: 6a3da1cb4853345fc18229f6
Added to database: 06/25/2026, 21:46:51 UTC
Last enriched: 06/25/2026, 22:03:44 UTC
Last updated: 06/29/2026, 03:51:10 UTC
Views: 5
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