CVE-2021-20265

Name: CVE-2021-20265
Creator: NVD / NIST
Published: 2021-03-10T16:15:16.61+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.5/10EPSS 0.34%

Last modified Jun 17, 2026

CVE-2021-20265 is a medium-severity vulnerability rated 5.5/10 on the CVSS scale. A flaw was found in the way memory resources were freed in the unix_stream_recvmsg function in the Linux kernel when a signal was pending. This flaw allows an unprivileged local user to crash the system by exhausting available memory. EPSS estimates a 0.34% chance of exploitation in the next 30 days.

Description

A flaw was found in the way memory resources were freed in the unix_stream_recvmsg function in the Linux kernel when a signal was pending. This flaw allows an unprivileged local user to crash the system by exhausting available memory. The highest threat from this vulnerability is to system availability.

Metrics

CVSS 3.1

5.5/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.34%

25.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Linux	Linux Kernel	All versions
Oracle	Tekelec Platform Distribution	>= 7.4.0, <= 7.7.1

References

https://bugzilla.redhat.com/show_bug.cgi?id=1908827Issue Tracking, Patch, Third Party Advisory
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=fa0dc04df259ba2df3ce1920e9690c7842f8fa4bPatch, Vendor Advisory
https://www.oracle.com/security-alerts/cpuoct2021.htmlPatch, Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1908827Issue Tracking, Patch, Third Party Advisory
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=fa0dc04df259ba2df3ce1920e9690c7842f8fa4bPatch, Vendor Advisory
https://www.oracle.com/security-alerts/cpuoct2021.htmlPatch, Third Party Advisory

Timeline

Published: Mar 10, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-20265?

How severe is CVE-2021-20265?

CVE-2021-20265 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.34% probability of exploitation in the next 30 days.

How do I fix CVE-2021-20265?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-20265?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST