CVE-2026-98637: Linux kernel · KVM: arm64: Do not clear VM-wide SVE feature on vCPU init failure
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in f0cd8ffae092cc1b9d7cfa9188ed5a88a374adcb : update Linux kernel when convenient.
Data as of 26 Oct 2026, 13:47 UTC
Rated Medium by Threat Radar's AI analysis · CVSS not yet scored by NVD
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 5% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in f0cd8ffae092cc1b9d7cfa9188ed5a88a374adcb, bd46b41f412fb81c50bac1a0929ec31320f3a807, a1b3c788ad31837e348075e93dbba3f447492776
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 f0cd8ffae092cc1b9d7cfa9188ed5a88a374adcb, bd46b41f412fb81c50bac1a0929ec31320f3a807 or a1b3c788ad31837e348075e93dbba3f447492776.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in– |
AI-suggested
A fix has been implemented in the Linux kernel as indicated by the presence of fixed versions (commit hashes). Users should update to a fixed kernel version containing these commits to remediate the issue. No additional mitigation steps are indicated.
Description
A vulnerability in the Linux kernel's KVM arm64 implementation involves improper handling of the Scalable Vector Extension (SVE) feature flag during virtual CPU initialization failures. Specifically, when pkvm_vcpu_init_sve() fails, it clears the KVM_ARM_VCPU_SVE flag but does not clear the KVM_ARCH_FLAG_GUEST_HAS_SVE flag, causing subsequent vCPUs to skip proper SVE setup and register with a NULL sve_state. This can lead to issues when the guest performs its first floating-point access.