CVE-2026-97555Hinoki check available

Kernel memory corruption via undersized DACL rewrite

Published Sep 25, 2026 · Updated Sep 25, 2026

Heap overflow in the Linux SMB client allows attackers to corrupt kernel memory during an owner or group DACL rewrite. id_mode_to_cifs_acl allocates from the original on-disk DACL size, while replace_sids_and_copy_aces can expand each ACE to a maximum-length cifs.idmap SID and write beyond that buffer. Triggering the overwrite requires a CIFS ACL rewrite with short source SIDs and longer replacement owner or group SIDs; published evidence demonstrates kernel-memory corruption but not code execution.

CVSS severityUnavailable
Unscored
EPSS probability0.52%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Heap overflow in the Linux SMB client allows attackers to corrupt kernel memory during an owner or group DACL rewrite. id_mode_to_cifs_acl allocates from the original on-disk DACL size, while replace_sids_and_copy_aces can expand each ACE to a maximum-length cifs.idmap SID and write beyond that buffer. Triggering the overwrite requires a CIFS ACL rewrite with short source SIDs and longer replacement owner or group SIDs; published evidence demonstrates kernel-memory corruption but not code execution.

The record

CVE
CVE-2026-97555
Published
Sep 25, 2026
Updated
Sep 25, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Sep 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=5.12
  2. Affected versionversion=bc3e9dd9d104ca1b75644eab87b38ce8a924aef4 <0ee150794c75bcd0be0e24ff3394f433cbae18cc
  3. Affected versionversion=bc3e9dd9d104ca1b75644eab87b38ce8a924aef4 <2a9aee9ef5622d58d8aafaa3263b3ffe70e2d9dd
  4. Affected versionversion=bc3e9dd9d104ca1b75644eab87b38ce8a924aef4 <7fa84c9ca690643f429ae2709584a47e74b572c9
  5. Affected versionversion=bc3e9dd9d104ca1b75644eab87b38ce8a924aef4 <fb736ab4fb8c4fdb8b2f9ccd3a62e03d11549ca1

What conditions does exploitation require?

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

What is affected?

The Linux Kernel Organization · Linuxversion=5.12; version=bc3e9dd9d104ca1b75644eab87b38ce8a924aef4 <0ee150794c75bcd0be0e24ff3394f433cbae18cc; version=bc3e9dd9d104ca1b75644eab87b38ce8a924aef4 <2a9aee9ef5622d58d8aafaa3263b3ffe70e2d9dd; version=bc3e9dd9d104ca1b75644eab87b38ce8a924aef4 <7fa84c9ca690643f429ae2709584a47e74b572c9; version=bc3e9dd9d104ca1b75644eab87b38ce8a924aef4 <fb736ab4fb8c4fdb8b2f9ccd3a62e03d11549ca1

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.

Activity data is delayed. The latest report is Sep 28, 2026.

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

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 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

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Your stack

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