Linux Kernel up to 6.6.79/6.12.16/6.13.4/6.14-rc3 io_uring privilege escalation

CVSS Meta Temp Score
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CTI Interest Score
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7.0$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in Linux Kernel up to 6.6.79/6.12.16/6.13.4/6.14-rc3. This vulnerability affects unknown code of the component io_uring. The manipulation results in an unknown weakness. This vulnerability is cataloged as CVE-2025-21863. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.6.79/6.12.16/6.13.4/6.14-rc3. It has been classified as problematic. Affected is an unknown function of the component io_uring. The impact remains unknown. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: io_uring: prevent opcode speculation sqe->opcode is used for different tables, make sure we santitise it against speculations.

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2025-21863 since 12/29/2024. There are neither technical details nor an exploit publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 236983 (Ubuntu 24.04 LTS / 24.10 : Linux kernel vulnerabilities (USN-7521-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.6.80, 6.12.17, 6.13.5 or 6.14-rc4 eliminates this vulnerability. Applying the patch b9826e3b26ec031e9063f64a7c735449c43955e4/506b9b5e8c2d2a411ea8fe361333f5081c56d23a/fdbfd52bd8b85ed6783365ff54c82ab7067bd61b/1e988c3fe1264708f4f92109203ac5b1d65de50b is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (236983) and CERT Bund (WID-SEC-2025-0545). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Google Container-Optimized OS
  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • Siemens SIMATIC S7
  • RESF Rocky Linux
  • SolarWinds Security Event Manager
  • Open Source Linux Kernel

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.0
VulDB Meta Temp Score: 7.0

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

ADP CISA Base Score: 7.8
ADP CISA Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Privilege escalation
CWE: Unknown
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 236983
Nessus Name: Ubuntu 24.04 LTS / 24.10 : Linux kernel vulnerabilities (USN-7521-1)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 6.6.80/6.12.17/6.13.5/6.14-rc4
Patch: b9826e3b26ec031e9063f64a7c735449c43955e4/506b9b5e8c2d2a411ea8fe361333f5081c56d23a/fdbfd52bd8b85ed6783365ff54c82ab7067bd61b/1e988c3fe1264708f4f92109203ac5b1d65de50b

Timelineinfo

12/29/2024 🔍
03/12/2025 +73 days 🔍
03/12/2025 +0 days 🔍
06/02/2026 +447 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-21863 (🔍)
GCVE (CVE): GCVE-0-2025-21863
GCVE (VulDB): GCVE-100-299544
CERT Bund: WID-SEC-2025-0545 - Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service

Entryinfo

Created: 03/12/2025 11:11
Updated: 06/02/2026 04:29
Changes: 03/12/2025 11:11 (56), 05/21/2025 01:39 (2), 12/14/2025 21:57 (7), 06/02/2026 04:29 (21)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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