VulnerabilityPublished 24 Oct 2026Updated 26 Oct 2026

CVE-2026-53236: kernel-rt security, bug fix, and enhancement update

Affects Linux kernelSource GCVE Database

Not known to be exploited : upgrade to 4.18.0-553.178.1.rt7.519.el8_10 soon.

Data as of 26 Oct 2026, 23:00 UTC

Severity

High

Rated High by Threat Radar's AI analysis · CVSS not yet scored by NVD

Patch: Available – fixed in 4.18.0-553.178.1.rt7.519.el8_10

Exploitation evidence

Disclosed: evidence found.
CVE published 24 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

almalinux-8

What to do

Upgrade the AlmaLinux to 4.18.0-553.178.1.rt7.519.el8_10.

Patches and advisories

access.redhat.com/errata/RHSA-2026:89082 (opens in a new tab)

Affected software

Product	Affected	Fixed in
AlmaLinux 8kernel-rt	Affected <4.18.0-553.178.1.rt7.519.el8_10	Fixed in 4.18.0-553.178.1.rt7.519.el8_10
AlmaLinux 8kernel-rt-core	Affected <4.18.0-553.178.1.rt7.519.el8_10	Fixed in 4.18.0-553.178.1.rt7.519.el8_10
AlmaLinux 8kernel-rt-debug	Affected <4.18.0-553.178.1.rt7.519.el8_10	Fixed in 4.18.0-553.178.1.rt7.519.el8_10
AlmaLinux 8kernel-rt-debug-core	Affected <4.18.0-553.178.1.rt7.519.el8_10	Fixed in 4.18.0-553.178.1.rt7.519.el8_10
AlmaLinux 8kernel-rt-debug-devel	Affected <4.18.0-553.178.1.rt7.519.el8_10	Fixed in 4.18.0-553.178.1.rt7.519.el8_10
AlmaLinux 8kernel-rt-debug-modules	Affected <4.18.0-553.178.1.rt7.519.el8_10	Fixed in 4.18.0-553.178.1.rt7.519.el8_10

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

A security update fixing these vulnerabilities is available in kernel-rt version 4.18.0-553.178.1.rt7.519.el8_10. Systems should be updated to this version or later and rebooted to apply the fixes. Red Hat recommends treating all kernel errata as security-relevant and applying updates promptly.

Description

Multiple security vulnerabilities affecting the kernel-rt (Real Time Linux Kernel) packages have been addressed in an important update. The update fixes issues including privilege restrictions on SO_ATTACH_FILTER, use-after-free bugs, race conditions, and validation errors across various kernel subsystems such as TCP, FUSE, network scheduling, USB, and SMB client. These vulnerabilities could impact system stability and security, especially in environments requiring high determinism. The update is available and requires a system reboot to take effect.

Impact

The vulnerabilities fixed in this update could allow unauthorized privilege escalation, use-after-free memory corruption, race conditions leading to system instability, and potential bypass of security checks in network and filesystem components. Given the kernel's critical role, these issues pose an important security risk to systems running affected versions of kernel-rt, especially in environments requiring real-time deterministic behavior.

Summary

The kernel-rt packages for Real Time Linux Kernel received an important security update addressing multiple CVEs including CVE-2026-53236 which restricts SO_ATTACH_FILTER socket option to privileged users. Other fixes include resolving use-after-free vulnerabilities in USB and IUCV subsystems, race conditions in writeback and network scheduling, checksum validation improvements in IPv4, and security enhancements in SELinux and SMB client handling. The update fixes these vulnerabilities in version 4.18.0-553.178.1.rt7.519.el8_10 and later.

References

Community reviews

Loading reviews…