CVE-2019-20396

Name: CVE-2019-20396
Creator: NVD / NIST
Published: 2020-01-22T22:15:10.47+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 1.91%

Last modified Jun 17, 2026

CVE-2019-20396 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. A segmentation fault is present in yyparse in libyang before v1.0-r1 due to a malformed pattern statement value during lys_parse_path parsing.. EPSS estimates a 1.91% chance of exploitation in the next 30 days.

Description

A segmentation fault is present in yyparse in libyang before v1.0-r1 due to a malformed pattern statement value during lys_parse_path parsing.

Metrics

CVSS 3.1

6.5/10

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

EPSS Probability

1.91%

77.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-119

Affected Software

Vendor	Product	Versions	Update
Cesnet	Libyang	0.11	R1
Cesnet	Libyang	0.12	R1
Cesnet	Libyang	0.13	R1
Cesnet	Libyang	0.14	R1
Cesnet	Libyang	0.15	R1
Cesnet	Libyang	0.16	R1

References

https://github.com/CESNET/libyang/commit/a1f17693904ed6fecc8902c747fc50a8f20e6af8Patch, Third Party Advisory
https://github.com/CESNET/libyang/compare/v0.16-r3...v1.0-r1Third Party Advisory
https://github.com/CESNET/libyang/issues/740Exploit, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2023/09/msg00019.html
https://github.com/CESNET/libyang/commit/a1f17693904ed6fecc8902c747fc50a8f20e6af8Patch, Third Party Advisory
https://github.com/CESNET/libyang/compare/v0.16-r3...v1.0-r1Third Party Advisory
https://github.com/CESNET/libyang/issues/740Exploit, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2023/09/msg00019.html

Timeline

Published: Jan 22, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2019-20396?

A segmentation fault is present in yyparse in libyang before v1.0-r1 due to a malformed pattern statement value during lys_parse_path parsing.

How severe is CVE-2019-20396?

CVE-2019-20396 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 1.91% probability of exploitation in the next 30 days.

How do I fix CVE-2019-20396?

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-2019-20396?

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

Scan your code now

Source: NVD / NIST