CVE-2024-42156

Clear-key disclosure via unwiped stack copies

Published Jul 30, 2024 · Updated May 11, 2026

Information disclosure in Linux allows local users with high privileges to recover clear-key data left in kernel stack memory after pkey IOCTLs. The s390 pkey conversion handlers copy clear-key structures onto the stack but return from failure paths without explicitly wiping every copy. Access requires a privileged local caller using the s390 protected-key interface, and the consequence is key-material disclosure without integrity or availability impact.

CVSS severity4.1
Medium
EPSS probability0.21%
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 allows local users with high privileges to recover clear-key data left in kernel stack memory after pkey IOCTLs. The s390 pkey conversion handlers copy clear-key structures onto the stack but return from failure paths without explicitly wiping every copy. Access requires a privileged local caller using the s390 protected-key interface, and the consequence is key-material disclosure without integrity or availability impact.

The record

CVE
CVE-2024-42156
Published
Jul 30, 2024
Updated
May 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1005
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Jul 30, 2024CVE publishedPublication date reported by the CVE source.
  2. May 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=5.4
  2. Affected versionversion=f2bbc96e7cfad3891b7bf9bd3e566b9b7ab4553d <7f6243edd901b75aaece326c90a1cc0dcb60cc3d
  3. Affected versionversion=f2bbc96e7cfad3891b7bf9bd3e566b9b7ab4553d <a891938947f4427f98cb1ce54f27223501efe750
  4. Affected versionversion=f2bbc96e7cfad3891b7bf9bd3e566b9b7ab4553d <d65d76a44ffe74c73298ada25b0f578680576073

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

The Linux Kernel Organization · Linuxversion=5.4; version=f2bbc96e7cfad3891b7bf9bd3e566b9b7ab4553d <7f6243edd901b75aaece326c90a1cc0dcb60cc3d; version=f2bbc96e7cfad3891b7bf9bd3e566b9b7ab4553d <a891938947f4427f98cb1ce54f27223501efe750; version=f2bbc96e7cfad3891b7bf9bd3e566b9b7ab4553d <d65d76a44ffe74c73298ada25b0f578680576073

Published CVSS scores

4.1NIST NVDCVSS:3.1/AV:L/AC:H/PR:H/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)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1005Data from Local System

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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