CVE-2025-21901

Kernel crash via freed RDMA device pointer

Published Apr 1, 2025 · Updated Aug 5, 2026

NULL pointer dereference in the Linux kernel 6.12 allows local users to crash the system through bnxt_re interrupt callbacks. The bnxt_re driver can call bnxt_re_stop_irq or bnxt_re_start_irq after device detachment has freed rdev, and the callbacks dereference that invalid device pointer. Reachability requires a local device-management or recovery path involving the affected RDMA driver; a remote RoCE or Ethernet peer cannot invoke the callbacks.

CVSS severity7.8
High
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

NULL pointer dereference in the Linux kernel 6.12 allows local users to crash the system through bnxt_re interrupt callbacks. The bnxt_re driver can call bnxt_re_stop_irq or bnxt_re_start_irq after device detachment has freed rdev, and the callbacks dereference that invalid device pointer. Reachability requires a local device-management or recovery path involving the affected RDMA driver; a remote RoCE or Ethernet peer cannot invoke the callbacks.

The record

CVE
CVE-2025-21901
Published
Apr 1, 2025
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-476, T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 1, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 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=6.12
  2. Affected versionversion=cc5b9b48d44756a87170f3901c6c2fd99e6b89b2 <8cb0eef46d70a99c88c26a1addb7fd955242e0e6
  3. Affected versionversion=cc5b9b48d44756a87170f3901c6c2fd99e6b89b2 <aed1bc673907e3df372b317c10ff2f3582f8bf1a
  4. Affected versionversion=cc5b9b48d44756a87170f3901c6c2fd99e6b89b2 <f0df225d12fcb049429fb5bf5122afe143c2dd15

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=6.12; version=cc5b9b48d44756a87170f3901c6c2fd99e6b89b2 <8cb0eef46d70a99c88c26a1addb7fd955242e0e6; version=cc5b9b48d44756a87170f3901c6c2fd99e6b89b2 <aed1bc673907e3df372b317c10ff2f3582f8bf1a; version=cc5b9b48d44756a87170f3901c6c2fd99e6b89b2 <f0df225d12fcb049429fb5bf5122afe143c2dd15

Published CVSS scores

7.8LinuxCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
5.5CISA-ADPCVSS: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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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
T1499Endpoint Denial of Service

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

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo