CVE-2026-97554Network attack vectorHinoki check available

Kernel stack disclosure via uninitialized SID mapping

Published Sep 25, 2026 · Updated Sep 25, 2026

Information disclosure in the SMB client in Linux before 7.2.7 allows attackers to expose kernel stack data via malformed directory entries. cifs_posix_to_fattr() ignores a posix_info_parse() failure, then sends uninitialized owner and group bytes through sid_to_id() and request_key(). The path requires a client to enumerate a POSIX SMB share from an untrusted server; disclosed bytes reach the local userspace idmap daemon.

CVSS severityUnavailable
Unscored
EPSS probability0.20%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Information disclosure in the SMB client in Linux before 7.2.7 allows attackers to expose kernel stack data via malformed directory entries. cifs_posix_to_fattr() ignores a posix_info_parse() failure, then sends uninitialized owner and group bytes through sid_to_id() and request_key(). The path requires a client to enumerate a POSIX SMB share from an untrusted server; disclosed bytes reach the local userspace idmap daemon.

The record

CVE
CVE-2026-97554
Published
Sep 25, 2026
Updated
Sep 25, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
network
Privileges
unauthenticated

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=0 <7.2.7
  2. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <c9a8b60ce140a68d172452f418137fc7ddbae7db
  3. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <da6e25842431982d5a53cf00d925b98c690f4467

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=0 <7.2.7; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <c9a8b60ce140a68d172452f418137fc7ddbae7db; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <da6e25842431982d5a53cf00d925b98c690f4467

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)
Vectornetwork
Privilegesunauthenticated
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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