PT-2020-1242 · Libyang · Libyang

Jvijtiuko · CVE-2019-20398 · Published 2020-01-22 · Updated 2023-09-20

Positive Technologies (AI Summary)

CVSS v3.1

6.5

Medium

Base vector

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

Name of the Vulnerable Software and Affected Versions libyang versions prior to 1.0-r3

Description A NULL pointer dereference issue is present in the lys extension instances free() function due to a copy of unresolved extensions in lys restr dup(). This can cause applications that use libyang to parse untrusted input yang files to crash.

Recommendations For versions prior to 1.0-r3, update to version 1.0-r3 or later to resolve the issue. As a temporary workaround, consider avoiding the use of lys extension instances free() and lys restr dup() functions when parsing untrusted input yang files until a patch is available. Restrict access to untrusted yang files to minimize the risk of exploitation.

Exploit

Fix

NULL Pointer Dereference

Weakness Enumeration

CWE-476

Related Identifiers

ALEA-2021:1906

CVE-2019-20398

DLA-3572-1

Affected Products

Libyang

References · 24

• 🔥 https://github.com/CESNET/libyang/issues/773 · Exploit
• https://github.com/CESNET/libyang/commit/7852b272ef77f8098c35deea6c6f09cb78176f08 · Patch
• https://bugzilla.redhat.com/show_bug.cgi?id=1793935 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2019-20398 · Security Note
• https://osv.dev/vulnerability/DEBIAN-CVE-2019-20398 · Vendor Advisory
• https://osv.dev/vulnerability/DLA-3572-1 · Vendor Advisory
• https://osv.dev/vulnerability/ALEA-2021:1906 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2019-20398 · Security Note
• https://osv.dev/vulnerability/CVE-2019-20398 · Vendor Advisory
• https://errata.almalinux.org/8/ALEA-2021-1906.html · Vendor Advisory
• https://ubuntu.com/security/CVE-2019-20398 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2019-20398 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2019-20398 · Vendor Advisory
• https://github.com/CESNET/libyang/compare/v1.0-r2...v1.0-r3 · Note
• https://vulners.com/cve/CVE-2019-20396 · Note