A stack consumption issue is present in libyang before v1.0-r1 due to the self-referential union type containing leafrefs. Applications that use libyang to parse untrusted input yang files may crash.

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.

An invalid memory access flaw is present in libyang before v1.0-r1 in the function resolvefeaturevalue() when an if-feature statement is used inside a list key node, and the feature used is not defined. Applications that use libyang to parse untrusted input yang files may crash.

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

A double-free is present in libyang before v1.0-r1 in the function yyparse() when an empty description is used. 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.

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.

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

A double-free is present in libyang before v1.0-r1 in the function yyparse() when an organization field is not terminated. 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.