CVE-2025-21798

Test crash via unchecked KUnit allocation

Published Feb 27, 2025 · Updated May 11, 2026

NULL pointer dereference in the Linux FireWire KUnit test allows local users to crash the test after a memory-allocation failure. The setup path in drivers/firewire/device-attribute-test.c dereferences test_state after kunit_kzalloc() without first rejecting a NULL return. The affected path requires execution of the FireWire KUnit test and an allocation failure; no remote trigger or impact outside that test path is documented.

CVSS severity5.5
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

NULL pointer dereference in the Linux FireWire KUnit test allows local users to crash the test after a memory-allocation failure. The setup path in drivers/firewire/device-attribute-test.c dereferences test_state after kunit_kzalloc() without first rejecting a NULL return. The affected path requires execution of the FireWire KUnit test and an allocation failure; no remote trigger or impact outside that test path is documented.

The record

CVE
CVE-2025-21798
Published
Feb 27, 2025
Updated
May 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-476
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 27, 2025CVE 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

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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=1c8506d62624fbc57db75414a387f365da8422e9 <352fafe97784e81a10a7c74bd508f71a19b53c2a
  2. Affected versionversion=1c8506d62624fbc57db75414a387f365da8422e9 <70fcb25472d90dd3b87cbee74b9eb68670b0c7b8
  3. Affected versionversion=1c8506d62624fbc57db75414a387f365da8422e9 <c6896bf4c611c3dd126f3e03685f2360a18b3d6f
  4. Affected versionversion=6.8

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=1c8506d62624fbc57db75414a387f365da8422e9 <352fafe97784e81a10a7c74bd508f71a19b53c2a; version=1c8506d62624fbc57db75414a387f365da8422e9 <70fcb25472d90dd3b87cbee74b9eb68670b0c7b8; version=1c8506d62624fbc57db75414a387f365da8422e9 <c6896bf4c611c3dd126f3e03685f2360a18b3d6f; version=6.8

Published CVSS scores

5.5NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-476NULL Pointer Dereference

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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