In function lysnodefree() in libyang <= v1.0.225, it asserts that the value of node->module can't be NULL. But in some cases, node->module can be null, which triggers a reachable assertion (CWE-617).

In function readyinleaf() in libyang <= v1.0.225, it doesn't check whether the value of retval->ext[r] is NULL. In some cases, it can be NULL, which leads to the operation of retval->ext[r]->flags that results in a crash.

In function extgetplugin() in libyang <= v1.0.225, it doesn't check whether the value of revision is NULL. If revision is NULL, the operation of strcmp(revision, extplugins[u].revision) will lead to a crash.

In function readyincontainer() in libyang <= v1.0.225, it doesn't check whether the value of retval->ext[r] is NULL. In some cases, it can be NULL, which leads to the operation of retval->ext[r]->flags that results in a crash.

A stack overflow in libyang <= v1.0.225 can cause a denial of service through function lyxmlparsemem(). lyxmlparseelem() function will be called recursively, which will consume stack space and lead to crash.