The webdriver for the Browser object expects an error object to be initialized when the webdriver_session_query function fails. But this function can fail for various reasons without an error description and then the wd->error will be NULL and trying to read from it will result in a crash.
Exploitability
AV:LAC:LPR:LUI:NScope
S:UImpact
C:NI:NA:L3.3/CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:LMemory Safety
Other