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Medium ALSA-2026:6036 3 CVEs

Moderate: kernel-rt security update

Published Mar 30, 2026 · Updated Oct 29, 2026

Ecosystem: AlmaLinux

Summary

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: Linux kernel: Use-After-Free vulnerability in ATM subsystem (CVE-2025-38180)
* kernel: macvlan: fix error recovery in macvlan_common_newlink() (CVE-2026-23209)
* kernel: net/sched: cls_u32: use skb_header_pointer_careful() (CVE-2026-23204)

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.

Fixed packages 10

ReleasePackageFixed in
AlmaLinux · 8 kernel-rt 4.18.0-553.115.1.rt7.456.el8_10
AlmaLinux · 8 kernel-rt-core 4.18.0-553.115.1.rt7.456.el8_10
AlmaLinux · 8 kernel-rt-debug 4.18.0-553.115.1.rt7.456.el8_10
AlmaLinux · 8 kernel-rt-debug-core 4.18.0-553.115.1.rt7.456.el8_10
AlmaLinux · 8 kernel-rt-debug-devel 4.18.0-553.115.1.rt7.456.el8_10
AlmaLinux · 8 kernel-rt-debug-modules 4.18.0-553.115.1.rt7.456.el8_10
AlmaLinux · 8 kernel-rt-debug-modules-extra 4.18.0-553.115.1.rt7.456.el8_10
AlmaLinux · 8 kernel-rt-devel 4.18.0-553.115.1.rt7.456.el8_10
AlmaLinux · 8 kernel-rt-modules 4.18.0-553.115.1.rt7.456.el8_10
AlmaLinux · 8 kernel-rt-modules-extra 4.18.0-553.115.1.rt7.456.el8_10

Vulnerabilities 3

  • High 7.8
    CVE-2025-38180

    net: atm: fix /proc/net/atm/lec handling

    In the Linux kernel, the following vulnerability has been resolved: net: atm: fix /proc/net/atm/lec handling /proc/net/atm/lec must ensure safety against dev_lec[] changes. It appears it had dev_put() calls without prior dev_hold(), leading to imbalance and U…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  • High 7.8
    CVE-2026-23209

    macvlan: fix error recovery in macvlan_common_newlink()

    In the Linux kernel, the following vulnerability has been resolved: macvlan: fix error recovery in macvlan_common_newlink() valis provided a nice repro to crash the kernel: ip link add p1 type veth peer p2 ip link set address 00:00:00:00:00:20 dev p1 ip link …

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  • High 7.1
    CVE-2026-23204

    net/sched: cls_u32: use skb_header_pointer_careful()

    In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_u32: use skb_header_pointer_careful() skb_header_pointer() does not fully validate negative @offset values. Use skb_header_pointer_careful() instead. GangMin Kim provided a rep…

    Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux

References

  • report
    https://access.redhat.com/security/cve/CVE-2025-38180
  • report
    https://access.redhat.com/security/cve/CVE-2026-23204
  • report
    https://access.redhat.com/security/cve/CVE-2026-23209
  • report
    https://bugzilla.redhat.com/2376376
  • report
    https://bugzilla.redhat.com/2439900
  • report
    https://bugzilla.redhat.com/2439931
  • advisory
    https://errata.almalinux.org/8/ALSA-2026-6036.html