CVE-2026-74395

Kernel crash via DEVX unwind NULL dereference

Published Aug 15, 2026 · Updated Aug 15, 2026

NULL-pointer dereference in the Linux kernel RDMA/mlx5 DEVX handler allows local users to crash the kernel during event-subscription error handling. MLX5_IB_METHOD_DEVX_SUBSCRIBE_EVENT links event_sub into sub_list before initializing fields consumed when eventfd_ctx_fdget fails, causing the unwind path to dereference an unset ev_file and mishandle xa_key_level1. Reachability requires mlx5 DEVX event subscription and a failing eventfd lookup; the bounded consequence is a kernel crash.

CVSS severityUnavailable
Unscored
EPSS probability0.18%
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 kernel RDMA/mlx5 DEVX handler allows local users to crash the kernel during event-subscription error handling. MLX5_IB_METHOD_DEVX_SUBSCRIBE_EVENT links event_sub into sub_list before initializing fields consumed when eventfd_ctx_fdget fails, causing the unwind path to dereference an unset ev_file and mishandle xa_key_level1. Reachability requires mlx5 DEVX event subscription and a failing eventfd lookup; the bounded consequence is a kernel crash.

The record

CVE
CVE-2026-74395
Published
Aug 15, 2026
Updated
Aug 15, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499.004
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Aug 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 15, 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=5.3
  2. Affected versionversion=7597385371425febdaa8c6a1da3625d4ffff16f5 <1025dc2f7ba29b04b8687790fa91f9cd1a53141e
  3. Affected versionversion=7597385371425febdaa8c6a1da3625d4ffff16f5 <43f8f7946814c8e5f464518246fdbc69b6e32326
  4. Affected versionversion=7597385371425febdaa8c6a1da3625d4ffff16f5 <5100febf8e9d6c8c5ba8dc6534c6a5e3376e5989
  5. Affected versionversion=7597385371425febdaa8c6a1da3625d4ffff16f5 <6e15b770461eeaa0ff73934922cb670a6a9db04e
  6. Affected versionversion=7597385371425febdaa8c6a1da3625d4ffff16f5 <78b9589fda266c71f0f9d0c858d4fa7381a890a5
  7. Affected versionversion=7597385371425febdaa8c6a1da3625d4ffff16f5 <7921821fc2b19c01588311f6e7468ae5b68b1f61
  8. Affected versionversion=7597385371425febdaa8c6a1da3625d4ffff16f5 <9be9aca28424228586fe9211c373ebdb826ebb6c
  9. Affected versionversion=7597385371425febdaa8c6a1da3625d4ffff16f5 <f345e744b6b087188cde2377da5cbe9713b61353

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=5.3; version=7597385371425febdaa8c6a1da3625d4ffff16f5 <1025dc2f7ba29b04b8687790fa91f9cd1a53141e; version=7597385371425febdaa8c6a1da3625d4ffff16f5 <43f8f7946814c8e5f464518246fdbc69b6e32326; version=7597385371425febdaa8c6a1da3625d4ffff16f5 <5100febf8e9d6c8c5ba8dc6534c6a5e3376e5989; version=7597385371425febdaa8c6a1da3625d4ffff16f5 <6e15b770461eeaa0ff73934922cb670a6a9db04e; version=7597385371425febdaa8c6a1da3625d4ffff16f5 <78b9589fda266c71f0f9d0c858d4fa7381a890a5; version=7597385371425febdaa8c6a1da3625d4ffff16f5 <7921821fc2b19c01588311f6e7468ae5b68b1f61; version=7597385371425febdaa8c6a1da3625d4ffff16f5 <9be9aca28424228586fe9211c373ebdb826ebb6c; version=7597385371425febdaa8c6a1da3625d4ffff16f5 <f345e744b6b087188cde2377da5cbe9713b61353

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.

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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
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

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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