CVE-2026-89921: Linux vulnerability

CVE-2026-89921: KVM: s390: Zero initialize data structures for inject_pfault_token

In the Linux kernel, the following vulnerability has been resolved: KVM: s390: Zero initialize data structures for inject_pfault_token __kvm_inject_pfault_token() only sets .type and .u.ext.ext_params2 of the on-stack struct kvm_s390_irq but the full ext substructure is copied into the cpu local variable on inject. ext_params and pad contain stale stack values. Interrupt delivery only uses ext_params2, so nothing leaks to the guest, but a host user can use the migration ioctls to get to the data. Fix by zero-initializing the irq struct. Do the same for the inti data structure.

UnknownCVSS not scoredNot KEV-listedUpdatedOct 19, 2026, 08:54 UTC (UTC+00:00)

Potential ATT&CK relevance

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CVE-2026-89921 mapping review

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Vulnerability profileCVE Program record

Severity: Unknown
CVSS: Not scored
Known Exploited: No
Published: Sep 16, 2026, 10:32 UTC (UTC+00:00)

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors

3Timeline events

0ADP providers

5Source links

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
Sep 11, 2026, 19:38 UTC (UTC+00:00)
CVE publishedCVE Program
The CVE record was published.
Sep 16, 2026, 10:32 UTC (UTC+00:00)
CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
Oct 19, 2026, 08:54 UTC (UTC+00:00)

Source materials

CVE List V5 sourceCVE List V5
https://git.kernel.org/stable/c/b8abc760fa18a389319d977834a30550b3ec18e8CVE reference, Linux
https://git.kernel.org/stable/c/9b046de62b8098af6e2ba820b125ec9dc5f162c8CVE reference, Linux
https://git.kernel.org/stable/c/134f235e0e8de54611a72d3cc3f63e5f31246baaCVE reference, Linux
https://git.kernel.org/stable/c/4e2c7f7cbc27418f9a290399b986c1b85ff93b90CVE reference, Linux

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus

LinuxLinux383d0b050106abecb82f43101cac94fa423af5cd, 383d0b050106abecb82f43101cac94fa423af5cd, 383d0b050106abecb82f43101cac94fa423af5cd, 383d0b050106abecb82f43101cac94fa423af5cdunaffected

LinuxLinux3.19, 0, 6.12.112, 6.18.52, 7.2.5, 7.3affected

Weakness

CWE details

No CWE listed

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