VulnerabilityPublished 12 Oct 2026Updated 24 Oct 2026

CVE-2026-98385: Linux kernel · sched/cache: Decouple sched_cache_group from mm to fix UAF

Affects Linux kernelSource CVE Database V5

Not known to be exploited · CVSS 7.8 High : upgrade to 852ecb6bc0bc0106f44f74ba3944524732486025 or 28f9c0e0a0b94c5d3e1b634db545f6e1f94858c5 soon.

Data as of 26 Oct 2026, 14:18 UTC

CVSS 3.1 base score

7.8High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.1% chance of exploitation in 30 days – higher than 7% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 852ecb6bc0bc0106f44f74ba3944524732486025, 28f9c0e0a0b94c5d3e1b634db545f6e1f94858c5

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Attack Vector: Local
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Local: The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 12 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.

What to do

Upgrade Linux kernel to 852ecb6bc0bc0106f44f74ba3944524732486025 or 28f9c0e0a0b94c5d3e1b634db545f6e1f94858c5.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ df0d98475954d655571979aa061ecb07d7e00392, < 852ecb6bc0bc0106f44f74ba3944524732486025	Fixed in 852ecb6bc0bc0106f44f74ba3944524732486025
LinuxLinux	Affected ≥ df0d98475954d655571979aa061ecb07d7e00392, < 28f9c0e0a0b94c5d3e1b634db545f6e1f94858c5	Fixed in 28f9c0e0a0b94c5d3e1b634db545f6e1f94858c5
LinuxLinux	Affected =7.2	Fixed in–

AI-suggested

A fix is available and has been applied in the Linux kernel. The vulnerability is resolved by decoupling sched_cache_group from mm_struct and managing its lifecycle with reference counting. Users should update to the fixed kernel versions identified by commits 852ecb6bc0bc0106f44f74ba3944524732486025 and 28f9c0e0a0b94c5d3e1b634db545f6e1f94858c5 or later. No additional mitigation steps are required once patched.

Description

CVE-2026-98385 is a use-after-free (UAF) vulnerability in the Linux kernel's scheduler cache subsystem. The issue arises because scheduling statistics (sched_cache_stat) are tied to the memory management structure (mm), and concurrent access during mm switching can lead to accessing freed memory. The vulnerability is addressed by decoupling sched_cache_group from mm_struct and managing its lifecycle independently with reference counting, preventing stale access. This fix also improves future flexibility in task grouping for scheduling.

Impact

This vulnerability allows a use-after-free condition in the Linux kernel scheduler subsystem, which can lead to memory corruption. The CVSS score of 7.8 indicates high severity with potential for confidentiality, integrity, and availability impacts. Exploitation could result in kernel crashes or privilege escalation due to corrupted scheduler state. However, no known exploits in the wild have been reported.

Summary

The Linux kernel scheduler cache grouping was originally tied to the mm_struct, with scheduling statistics embedded within it. During concurrent operations, a task switching its mm could cause another CPU running account_mm_sched() to access the old, freed mm's scheduling stats, leading to a use-after-free condition. The patch decouples sched_cache_group from mm_struct, renames sched_cache_stat to sched_cache_group, and manages it as a refcounted object separate from mm_struct. This prevents use-after-free by ensuring tasks hold references to valid sched_cache_group objects even when switching mm. The change also enables more flexible future grouping strategies beyond mm-based grouping.

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Oct 2026, 09:39 UTC

Technical details

References

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