CVE-2026-31612Network attack vector

Unauthenticated heap disclosure via unchecked EA length

Published Apr 24, 2026 · Updated Apr 24, 2026

Information disclosure in Linux Kernel ksmbd allows remote attackers to read uninitialized heap data through a crafted SMB request. smb2_get_ea() trusts the request's EaNameLength as the strncmp() comparison length without confirming that the name occupies that much received data. The ksmbd SMB server must be enabled and network-reachable; no authentication or user interaction is required, and the effect is limited to heap-data disclosure.

CVSS severity7.5
High
EPSS probability0.41%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Linux Kernel ksmbd allows remote attackers to read uninitialized heap data through a crafted SMB request. smb2_get_ea() trusts the request's EaNameLength as the strncmp() comparison length without confirming that the name occupies that much received data. The ksmbd SMB server must be enabled and network-reachable; no authentication or user interaction is required, and the effect is limited to heap-data disclosure.

The record

CVE
CVE-2026-31612
Published
Apr 24, 2026
Updated
Apr 24, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 24, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 24, 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=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <243b206bcb5a7137e8bddd57b2eec81e1ebd3859
  2. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <3363a770b193f555f29d76ddf4ced3305c0ccf6d
  3. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <551dfb15b182abad4600eaf7b37e6eb7000d5b1b
  4. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <dfc6878d14acafffbe670bf2576620757a10a3d8

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <243b206bcb5a7137e8bddd57b2eec81e1ebd3859; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <3363a770b193f555f29d76ddf4ced3305c0ccf6d; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <551dfb15b182abad4600eaf7b37e6eb7000d5b1b; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <dfc6878d14acafffbe670bf2576620757a10a3d8

Published CVSS scores

7.5Linux kernel CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

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.

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No observations available

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

Weakness, pattern, technique

T1190Exploit Public-Facing Application

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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