VulnerabilityPublished 6 Oct 2026Updated 19 Oct 2026

CVE-2026-98248: Linux kernel · arm64: percpu: Fix LSE operations on {8,16}-bit types

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in d69ab4480e49bf925f4781afcc9f284affcb96b6 : update Linux kernel when convenient.

Data as of 26 Oct 2026, 13:47 UTC

Severity

Medium

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in d69ab4480e49bf925f4781afcc9f284affcb96b6, 390742871a723b52de9b92a94c0d1c85a2531e3e, 843ace1d0a39e9b1cfcbfb3856a7b0fbdd9cd003 +1

Exploitation evidence

Disclosed: evidence found.
CVE published 6 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 d69ab4480e49bf925f4781afcc9f284affcb96b6, 390742871a723b52de9b92a94c0d1c85a2531e3e, 843ace1d0a39e9b1cfcbfb3856a7b0fbdd9cd003 or 8cf2093f5372952a9ebc805c418d45df7112cd14.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ 959bf2fd03b59fc107584c21425f3dc73c49f762, < d69ab4480e49bf925f4781afcc9f284affcb96b6	Fixed in d69ab4480e49bf925f4781afcc9f284affcb96b6
LinuxLinux	Affected ≥ 959bf2fd03b59fc107584c21425f3dc73c49f762, < 390742871a723b52de9b92a94c0d1c85a2531e3e	Fixed in 390742871a723b52de9b92a94c0d1c85a2531e3e
LinuxLinux	Affected ≥ 959bf2fd03b59fc107584c21425f3dc73c49f762, < 843ace1d0a39e9b1cfcbfb3856a7b0fbdd9cd003	Fixed in 843ace1d0a39e9b1cfcbfb3856a7b0fbdd9cd003
LinuxLinux	Affected ≥ 959bf2fd03b59fc107584c21425f3dc73c49f762, < 8cf2093f5372952a9ebc805c418d45df7112cd14	Fixed in 8cf2093f5372952a9ebc805c418d45df7112cd14
LinuxLinux	Affected =5.0	Fixed in–

AI-suggested

A fix is available and has been applied in the Linux kernel source code as indicated by the fixed commit hashes. Users should update their Linux kernel to a version that includes these fixes to resolve the issue.

Description

A vulnerability in the Linux kernel arm64 architecture affects the implementation of LSE operations on 8-bit and 16-bit types in per-CPU code. The issue arises because the assembly code does not correctly use the size suffix ('sfx') for LSE instructions, causing 8- and 16-bit operations to incorrectly read and write 32 bits of memory. This flaw has been fixed by appending the correct size suffix to the LSE instruction in the kernel code.

Impact

The vulnerability causes incorrect memory reads and writes for 8-bit and 16-bit per-CPU operations on arm64 Linux kernels, potentially leading to data corruption or unexpected behavior in kernel code relying on these operations. There is no indication of exploitation in the wild or direct security compromise from this flaw.

Summary

CVE-2026-98248 addresses a flaw in the Linux kernel's arm64 per-CPU code where the assembly functions __percpu_##name##_case_##sz() and __percpu_##name##_return_case_##sz() omit the 'sfx' macro argument when forming LSE instructions. Without this suffix, the instructions default to 32-bit memory operations, leading to incorrect memory access for 8-bit and 16-bit operations. The fix involves appending the 'sfx' suffix to the 'op_lse' instruction to ensure correct operation size, while 'op_llsc' remains unchanged as it is a register-register operation.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Oct 2026, 12:08 UTC

Technical details

References

Community reviews

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