CVE-2025-21980

Kernel crash via GRED error-path NULL dereference

Published Apr 1, 2025 · Updated May 11, 2026

NULL pointer dereference in the GRED scheduler in the Linux kernel allows local users to crash the kernel during allocation failure. If kzalloc in gred_init fails, the error path calls gred_destroy and gred_offload, which passes the NULL table->opt pointer to memset. Reachability requires local access and a gred_init allocation failure; the published impact is limited to a kernel crash, with no reported data access or modification.

CVSS severity5.5
Medium
EPSS probability0.19%
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 GRED scheduler in the Linux kernel allows local users to crash the kernel during allocation failure. If kzalloc in gred_init fails, the error path calls gred_destroy and gred_offload, which passes the NULL table->opt pointer to memset. Reachability requires local access and a gred_init allocation failure; the published impact is limited to a kernel crash, with no reported data access or modification.

The record

CVE
CVE-2025-21980
Published
Apr 1, 2025
Updated
May 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-476, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 1, 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=5.16
  2. Affected versionversion=f25c0515c521375154c62c72447869f40218c861 <0f0a152957d64ce45b4c27c687e7d087e8f45079
  3. Affected versionversion=f25c0515c521375154c62c72447869f40218c861 <115ef44a98220fddfab37a39a19370497cd718b9
  4. Affected versionversion=f25c0515c521375154c62c72447869f40218c861 <5f996b4f80c2cef1f9c77275055e7fcba44c9199
  5. Affected versionversion=f25c0515c521375154c62c72447869f40218c861 <68896dd50180b38ea552e49a6a00b685321e5769
  6. Affected versionversion=f25c0515c521375154c62c72447869f40218c861 <d02c9acd68950a444acda18d514e2b41f846cb7f

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=5.16; version=f25c0515c521375154c62c72447869f40218c861 <0f0a152957d64ce45b4c27c687e7d087e8f45079; version=f25c0515c521375154c62c72447869f40218c861 <115ef44a98220fddfab37a39a19370497cd718b9; version=f25c0515c521375154c62c72447869f40218c861 <5f996b4f80c2cef1f9c77275055e7fcba44c9199; version=f25c0515c521375154c62c72447869f40218c861 <68896dd50180b38ea552e49a6a00b685321e5769; version=f25c0515c521375154c62c72447869f40218c861 <d02c9acd68950a444acda18d514e2b41f846cb7f

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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 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
T1499.004Application or System Exploitation

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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