CVE-2026-98463

Source
https://cve.org/CVERecord?id=CVE-2026-98463
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98463.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-98463
Downstream
Published
2026-10-18T15:15:15Z
Modified
2026-10-20T02:30:54Z
Summary
sched_ext: Derive SCX_RQ_IN_WAKEUP from the core enqueue flags
Details

In the Linux kernel, the following vulnerability has been resolved:

sched_ext: Derive SCX_RQ_IN_WAKEUP from the core enqueue flags

schedule_deferred_locked() skips scheduling a deferred action while SCX_RQ_IN_WAKEUP is set and relies on the task_woken_scx() call that follows a wakeup enqueue to run it. enqueue_task_scx() sets the flag from the merged enqueue flags, which include the flags stashed for a remote activation. move_remote_task_to_local_dsq() thus sets SCX_RQ_IN_WAKEUP on the destination rq when the moved task was woken up, although no task_woken_scx() follows that activation.

An IMMED insert into a busy destination requests a local reenqueue during that enqueue. The request gets linked but not scheduled and stays pending until an unrelated wakeup or preemption on that CPU runs the deferred actions. The IMMED task sits behind the running task in the meantime. If nothing runs them before the scheduler is disabled, the request outlives the scheduler and points into its freed per-cpu area, which the next scheduler dereferences from run_deferred().

Test the core enqueue flags for the wakeup bit. Only the core's wakeup path is followed by task_woken_scx().

Database specific
{
    "cna_assigner":  "Linux",
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98463.json"
}
References

Affected packages

Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Affected ranges

Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
997967adf10ce26c3e7bd89598b3ded62b943052
Fixed
6c401ae426e20e53a3398a8e79afd0964c0f5110
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
57ccf5ccdc56954f2a91a7f66684fd31c566bde5
Fixed
3fdf2ceb31e8aff77451e468bc8409e10587916a
Fixed
df5cdc2c832ca4e8a6d774596b9005558761a403
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
6.18.19
Fixed
6.18.55
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
6.19.9
Fixed
6.20
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
ee502c056c4c9cce4c132ccb588e06ffe5b831c1

Affected versions

v6.*
v6.18.19
v6.18.20
v6.18.21
v6.18.22
v6.18.23
v6.18.24
v6.18.25
v6.18.26
v6.18.27
v6.18.28
v6.18.29
v6.18.30
v6.18.31
v6.18.32
v6.18.33
v6.18.34
v6.18.35
v6.18.36
v6.18.37
v6.18.38
v6.18.39
v6.18.40
v6.18.41
v6.18.42
v6.18.43
v6.18.44
v6.18.45
v6.18.46
v6.18.47
v6.18.48
v6.18.49
v6.18.50
v6.18.51
v6.18.52
v6.18.53
v6.18.54
v6.19.10
v6.19.11
v6.19.12
v6.19.13
v6.19.14
v6.19.9

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98463.json"

Linux / Kernel

Package

Name
Kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
6.18.55
Type
ECOSYSTEM
Events
Introduced
6.19.0
Fixed
7.2.9

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98463.json"