PT-2021-4113 · Libyang+2 · Libyang+2

Zounathan · Published 2021-03-08 · Updated 2022-09-12 · CVE-2021-28906

Positive Technologies (AI Summary)

CVSS v3.1

7.5

High

Base vector

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

Name of the Vulnerable Software and Affected Versions libyang versions prior to 1.0.226

Description The issue is related to the function read yin leaf() in the libyang library, which fails to check if the value of retval->ext[r] is NULL. This can lead to a crash when attempting to access retval->ext[r]->flags when retval->ext[r] is NULL. The vulnerability can be exploited by a remote attacker to cause a denial of service.

Recommendations For libyang versions prior to 1.0.226, update to version 1.0.226 or later to resolve the issue. As a temporary workaround, consider adding a NULL check for retval->ext[r] before accessing its members to prevent the crash.

Exploit

Fix

Unchecked Return Value

Weakness Enumeration

CWE-252

Related Identifiers

BDU:2021-04703

CVE-2021-28906

OPENSUSE-SU-2022_3245-1

SUSE-SU-2022:3245-1

Affected Products

Debian

Suse

Libyang

References · 20

• 🔥 https://github.com/CESNET/libyang/issues/1455 · Exploit
• https://nvd.nist.gov/vuln/detail/CVE-2021-28906 · Security Note
• https://security.gentoo.org/glsa/202107-54 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2021-28906 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2021-28906 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2021-28906 · Security Note
• https://ubuntu.com/security/CVE-2021-28906 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2022:3245-1 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2021-28906 · Vendor Advisory
• https://bdu.fstec.ru/vul/2021-04703 · Security Note
• https://osv.dev/vulnerability/CVE-2021-28906 · Vendor Advisory
• https://bugzilla.suse.com/1186374 · Note
• https://bugzilla.suse.com/1186378 · Note
• https://suse.com/security/cve/CVE-2021-28903 · Note
• https://suse.com/security/cve/CVE-2021-28902 · Note