CVE-2026-98866: Linux kernel · sched/cache: Introduce task_struct->sched_cache_grp to fix UAF
Affects Linux kernelSource CVE Database V5
Not known to be exploited : upgrade to b636fef85bda7d1bab9c0a45067ab1508d79d946 or 9436130e6da72af63289a4acb3aa0c1df07a3928 soon.
Data as of 26 Oct 2026, 12:55 UTC
Rated High by Threat Radar's AI analysis · CVSS not yet scored by NVD
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in b636fef85bda7d1bab9c0a45067ab1508d79d946, 9436130e6da72af63289a4acb3aa0c1df07a3928
Exploitation evidence
Disclosed: evidence found.
CVE published 18 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.
What to do
Upgrade Linux kernel to b636fef85bda7d1bab9c0a45067ab1508d79d946 or 9436130e6da72af63289a4acb3aa0c1df07a3928.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in– |
Red Hatredhat/kernelpkg:rpm/redhat/kernelOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available and has been applied in the Linux kernel versions identified by commits b636fef85bda7d1bab9c0a45067ab1508d79d946 and 9436130e6da72af63289a4acb3aa0c1df07a3928. Users and administrators should update to these fixed versions or later to remediate the vulnerability.
Description
CVE-2026-98866 is a use-after-free (UAF) vulnerability in the Linux kernel scheduler. It was fixed by introducing a new pointer task_struct->sched_cache_grp to decouple scheduler hot-path accesses from the memory management structure mm_struct. This change prevents the scheduler from accessing freed memory when switching memory contexts, addressing a reported UAF condition.