SB2020012248 - Multiple vulnerabilities in CESNET libyang

CSH
CYBERSECURITY HELP
Sign In REGISTER

Main Vulnerability Database SB2020012248

SB2020012248 - Multiple vulnerabilities in CESNET libyang

Published: January 22, 2020 Updated: October 8, 2021

Security Bulletin ID SB2020012248
CSH Severity
High
Patch available
YES
Number of vulnerabilities 3
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

High 33% Medium 67%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 3 vulnerabilities.


1) Buffer overflow (CVE-ID: CVE-2019-20391)

The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.

An invalid memory access flaw is present in libyang before v1.0-r3 in the function resolve_feature_value() when an if-feature statement is used inside a bit. Applications that use libyang to parse untrusted input yang files may crash.


2) Double Free (CVE-ID: CVE-2019-20394)

The vulnerability allows a remote non-authenticated attacker to execute arbitrary code.

A double-free is present in libyang before v1.0-r3 in the function yyparse() when a type statement in used in a notification statement. Applications that use libyang to parse untrusted input yang files may be vulnerable to this flaw, which would cause a crash or potentially code execution.


3) NULL pointer dereference (CVE-ID: CVE-2019-20398)

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error in libyang before v1.0-r3 in the function lys_extension_instances_free() due to a copy of unresolved extensions in lys_restr_dup(). Applications that use libyang to parse untrusted input yang files may crash. A remote attacker can perform a denial of service (DoS) attack.


Remediation

Install update from vendor's website.

References