CVE-2019-20398: Null Pointer Dereference
A NULL pointer dereference is present in libyang before v1.0-r3 in the function lysextensioninstancesfree() due to a copy of unresolved extensions in lysrestrdup(). Applications that use libyang to parse untrusted input yang files may crash.
Other sources
A NULL pointer dereference is present in libyang up to version v1.0-r3 in function lysextensioninstancesfree() due to copy of unresolved extensions in lysrestrdup(). Applications that use libyang to parse untrusted input yang files may crash.
Upstream fix: https://github.com/CESNET/libyang/commit/7852b272ef77f8098c35deea6c6f09cb78176f08
Upstream issue: https://github.com/CESNET/libyang/issues/773
— Red Hat
Affected Software
Remediation
Patch Available
Event History
Frequently Asked Questions
What is the severity of CVE-2019-20398?
CVE-2019-20398 is classified as a high severity vulnerability due to the potential for application crashes from a NULL pointer dereference.
How do I fix CVE-2019-20398?
To fix CVE-2019-20398, you should upgrade libyang to version 1.0-r3 or later.
Which versions of libyang are affected by CVE-2019-20398?
CVE-2019-20398 affects libyang versions prior to v1.0-r3, including versions up to and including 1.0.
What type of issue is identified in CVE-2019-20398?
CVE-2019-20398 is a NULL pointer dereference issue that can lead to application crashes when parsing untrusted YANG files.
Can I use older versions of libyang without addressing CVE-2019-20398?
Using older versions of libyang without addressing CVE-2019-20398 is risky, as they are vulnerable to crashes when processing untrusted input.