CVE-2026-97564

Root-context identity manipulation via unvetted descriptions

Published Sep 25, 2026 · Updated Sep 25, 2026

Improper input validation in Linux 3.0 and later allows local users to inject authority-bearing fields into CIFS idmap requests. The cifs.idmap key type lacks a vet_description hook, so request_key or add_key can supply owner, group, UID, and GID fields that the helper treats as kernel-originated. Exploitation requires local key-syscall access and a configured CIFS idmap upcall; the crafted values are then consumed during root-context identity mapping.

CVSS severityUnavailable
Unscored
EPSS probability0.21%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Linux 3.0 and later allows local users to inject authority-bearing fields into CIFS idmap requests. The cifs.idmap key type lacks a vet_description hook, so request_key or add_key can supply owner, group, UID, and GID fields that the helper treats as kernel-originated. Exploitation requires local key-syscall access and a configured CIFS idmap upcall; the crafted values are then consumed during root-context identity mapping.

The record

CVE
CVE-2026-97564
Published
Sep 25, 2026
Updated
Sep 25, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
local
Privileges
authenticated

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=3.0
  2. Affected versionversion=4d79dba0e00749fa40de8ef13a9b85ce57a1603b <1d3b24b16a0b013792e8f1e3ed060f0b46f537d1
  3. Affected versionversion=4d79dba0e00749fa40de8ef13a9b85ce57a1603b <96751028c0d4dec785709ea3eb0ab38a4f2ded96
  4. Affected versionversion=4d79dba0e00749fa40de8ef13a9b85ce57a1603b <d9d7eeb0cea5b55b82888f443622fd8d4ee064f3
  5. Affected versionversion=4d79dba0e00749fa40de8ef13a9b85ce57a1603b <e5964064e3fbe6325893408faff08ca33de0e2c3

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=3.0; version=4d79dba0e00749fa40de8ef13a9b85ce57a1603b <1d3b24b16a0b013792e8f1e3ed060f0b46f537d1; version=4d79dba0e00749fa40de8ef13a9b85ce57a1603b <96751028c0d4dec785709ea3eb0ab38a4f2ded96; version=4d79dba0e00749fa40de8ef13a9b85ce57a1603b <d9d7eeb0cea5b55b82888f443622fd8d4ee064f3; version=4d79dba0e00749fa40de8ef13a9b85ce57a1603b <e5964064e3fbe6325893408faff08ca33de0e2c3

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)
Vectorlocal
Privilegesauthenticated
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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