CVE-2026-89587Hinoki check available

Kernel stack overwrite via oversized ACPI buffers

Published Sep 11, 2026 · Updated Sep 11, 2026

Stack-based buffer overflow in Linux 5.17 allows attackers to overwrite kernel stack memory through oversized ACPI _DSM buffers. The ACPI PFR update driver's query_capability() function passes each firmware-reported length to memcpy() while copying into four fixed 16-byte fields in a stack-allocated structure. Reachability requires platform firmware that exposes the PFR update _DSM interface and returns an oversized capability buffer when the ioctl queries it; the demonstrated consequence is an out-of-bounds kernel-stack write.

CVSS severityUnavailable
Unscored
EPSS probability0.14%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Stack-based buffer overflow in Linux 5.17 allows attackers to overwrite kernel stack memory through oversized ACPI _DSM buffers. The ACPI PFR update driver's query_capability() function passes each firmware-reported length to memcpy() while copying into four fixed 16-byte fields in a stack-allocated structure. Reachability requires platform firmware that exposes the PFR update _DSM interface and returns an oversized capability buffer when the ioctl queries it; the demonstrated consequence is an out-of-bounds kernel-stack write.

The record

CVE
CVE-2026-89587
Published
Sep 11, 2026
Updated
Sep 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Sep 11, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 11, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0db89fa243e5edc5de38c88b369e4c3755c5fb74 <15d2b7f38f95d28652170344f39ee492c55e567c
  2. Affected versionversion=0db89fa243e5edc5de38c88b369e4c3755c5fb74 <6d4ed2fd022bc862b156e53aae163b61259e1caa
  3. Affected versionversion=0db89fa243e5edc5de38c88b369e4c3755c5fb74 <a2151624b55029dad0ca7efd17fb83a0461c8843
  4. Affected versionversion=0db89fa243e5edc5de38c88b369e4c3755c5fb74 <ced45be0073a8a31b30b4a7f68cd3a15734515de
  5. Affected versionversion=5.17

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=0db89fa243e5edc5de38c88b369e4c3755c5fb74 <15d2b7f38f95d28652170344f39ee492c55e567c; version=0db89fa243e5edc5de38c88b369e4c3755c5fb74 <6d4ed2fd022bc862b156e53aae163b61259e1caa; version=0db89fa243e5edc5de38c88b369e4c3755c5fb74 <a2151624b55029dad0ca7efd17fb83a0461c8843; version=0db89fa243e5edc5de38c88b369e4c3755c5fb74 <ced45be0073a8a31b30b4a7f68cd3a15734515de; version=5.17

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo