CVE-2020-25656: A flaw was found in the Linux kernel. A use-after-free was found in the way the console subsystem was using ioctls KDGKBSENT and KDSKBSENT. A local user could use this flaw to get read memory access out of bounds. The highest threat from this vulnerability is to data confidentiality.

Overview

Severity
Medium (CVSS 4.1)
CVSS Vector
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N
Exploit Status
Not Exploited
Patch Tuesday
2020-Dec
Released
2020-12-05
EPSS Score
0.01% (percentile: 1.4%)

FAQ

Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability? One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.

Affected Products (1)

Mariner

  • cm1 kernel 5.4.91-1 on CBL Mariner 1.0

Revision History

  • 2020-12-05: Information published.