CVE-2025-37890VulnerabilityPublished 24 Sep 2025Updated 30 Jul 2026

Red Hat Security Advisory: kpatch-patch-4_18_0-372_118_1, kpatch-patch-4_18_0-372_131_1, kpatch-patch-4_18_0-372_137_1, and kpatch-patch-4_18_0-372_145_1 security update

Affects Red HatSource GCVE Database

Mentioned vulnerabilities

Not known to be exploited.

Data as of 25 Oct 2026, 19:02 UTC

Severity

High

Rated by Threat Radar · No CVSS score from NVD or the CNA

EPSS: 0.2% chance of exploitation in 30 days – higher than 12% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

Exploitation evidence

Disclosed: evidence found.
CVE published 24 Sep 2025
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 2026-10-25.

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 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.

What to do

Affected software

Product	Affected	Fixed in
Red Hat Product Security Red Hat	Affected Red Hat Red Hat Enterprise Linux Red Hat Enterprise Linux BaseOS E4S (v.8.6) src kpatch-patch-4_18_0-372_118_1-0:1-11.el8_6.src	Fixed in–

AI-suggested

Red Hat has released updated kpatch-patch packages for the affected kernel version 4.18.0-372.118.1.el8_6. Users should apply these updates as provided by Red Hat and reboot their systems to ensure the patches take effect. For detailed update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigations are indicated by the vendor advisory.

Description

This is a kernel live patch module which can be loaded by the kpatch command line utility to modify the code of a running kernel. This patch module is targeted for kernel-4.18.0-372.118.1.el8_6. Security Fix(es): * kernel: net_sched: hfsc: Fix a UAF vulnerability in class with netem as child qdisc (CVE-2025-37890) * kernel: net_sched: hfsc: Address reentrant enqueue adding class to eltree twice (CVE-2025-38001) * kernel: sch_hfsc: Fix qlen accounting bug when using peek in hfsc_enqueue() (CVE-2025-38000) * kernel: net/sched: Always pass notifications when child class becomes empty (CVE-2025-38350) * kernel: i2c/designware: Fix an initialization issue (CVE-2025-38380) 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.

Impact

The vulnerabilities include a use-after-free condition and logic errors in kernel scheduling components that could lead to instability or potential privilege escalation if exploited. The initialization issue in the i2c/designware driver may affect device operation. The overall security impact is rated as Important by Red Hat, indicating significant risk if unpatched. No known exploits in the wild have been reported at this time.

Summary

The advisory covers security fixes for the kpatch live patch module targeting kernel-4.18.0-372.118.1.el8_6 in Red Hat Enterprise Linux 8.6. It addresses five CVEs: CVE-2025-37890 (use-after-free in net_sched hfsc class with netem child qdisc), CVE-2025-38001 (reentrant enqueue adding class to eltree twice), CVE-2025-38000 (queue length accounting bug in hfsc_enqueue), CVE-2025-38350 (notification passing when child class becomes empty), and CVE-2025-38380 (initialization issue in i2c/designware). These vulnerabilities affect kernel scheduling and device initialization components. The advisory provides updated kpatch-patch packages and requires rebooting the system to apply the fixes.

CWE-416Use After Free (opens in a new tab)
Variant weaknessLikelihood of exploit: HighCWE Top 25 (2025): #7
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
Architecture and Design · Language Selection
Choose a language that provides automatic memory management.
Implementation · Attack Surface Reduction
When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
OWASP Cheat Sheets
XML Security (opens in a new tab)
Mass Assignment (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.1 (opens in a new tab)
V5.1.4 (opens in a new tab)
V5.1.3 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-908Use of Uninitialized Resource (opens in a new tab)
Base weaknessLikelihood of exploit: Medium
The product uses or accesses a resource that has not been initialized.
Implementation
Explicitly initialize the resource before use. If this is performed through an API function or standard procedure, follow all required steps.
Implementation
Pay close attention to complex conditionals that affect initialization, since some branches might not perform the initialization.
Implementation
Avoid race conditions (CWE-362) during initialization routines.
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 25 Jun 2026, 05:01 UTC

WeaknessesCWE-416, CWE-908

Technical details

References

Community reviews

Related threats