CVE-2020-29129

Name: CVE-2020-29129
Creator: NVD / NIST
Published: 2020-11-26T20:15:10.737+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 4.3/10EPSS 1.44%

Last modified Jun 17, 2026

CVE-2020-29129 is a medium-severity vulnerability rated 4.3/10 on the CVSS scale. ncsi.c in libslirp through 4.3.1 has a buffer over-read because it tries to read a certain amount of header data even if that exceeds the total packet length.. EPSS estimates a 1.44% chance of exploitation in the next 30 days.

Description

ncsi.c in libslirp through 4.3.1 has a buffer over-read because it tries to read a certain amount of header data even if that exceeds the total packet length.

Metrics

CVSS 3.1

4.3/10

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

EPSS Probability

1.44%

69.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-125

Affected Software

Vendor	Product	Versions
Libslirp Project	Libslirp	<= 4.3.1
Fedoraproject	Fedora	32
Fedoraproject	Fedora	33
Debian	Debian Linux	10.0

References

http://www.openwall.com/lists/oss-security/2020/11/27/1Mailing List, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/45S5IHSWYITJKMRT23HCHJQDI674AMTQ/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OPCOHDEONMHH6QPJZKRLLCNRGRYODG7X/
https://lists.freedesktop.org/archives/slirp/2020-November/000115.htmlMailing List, Vendor Advisory
http://www.openwall.com/lists/oss-security/2020/11/27/1Mailing List, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/45S5IHSWYITJKMRT23HCHJQDI674AMTQ/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OPCOHDEONMHH6QPJZKRLLCNRGRYODG7X/
https://lists.freedesktop.org/archives/slirp/2020-November/000115.htmlMailing List, Vendor Advisory

Timeline

Published: Nov 26, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-29129?

ncsi.c in libslirp through 4.3.1 has a buffer over-read because it tries to read a certain amount of header data even if that exceeds the total packet length.

How severe is CVE-2020-29129?

CVE-2020-29129 has a CVSS score of 4.3/10 (MEDIUM severity). The EPSS model estimates a 1.44% probability of exploitation in the next 30 days.

How do I fix CVE-2020-29129?

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-2020-29129?

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

Scan your code now

Source: NVD / NIST