CVE-2026-118938: Fickling check_safety() bypass: dotted __qualname__ in STACK_GLOBAL resolves a class-method attribute path that evades call analysis

In Trail of Bits fickling through 0.1.12, a pickle STACKGLOBAL operand carrying a dotted qualname (for example "Values.readfile") is resolved by pickle's findclass through getattribute to an arbitrary attribute path rather than to a module-level function. Fickling records only the leading component of the name in its import tracking and renders the operation as a plain import (for instance, 'python -m fickling' displays it as 'from optparse import Values.readfile'), so the trailing attribute reference is never analyzed as a call. The OvertlyBadEvals analysis pass does not flag it, and checksafety() returns LIKELYSAFE with zero findings. This allows an attacker to reach a class method that performs code execution: optparse.Values.readfile executes exec(open(filename).read(), vars), achieving arbitrary code execution when the crafted pickle is loaded through fickling.load(), which chains checksafety() into pickle.loads() as an explicit security gate. optparse is present in all current CPython 3.x releases (deprecated as of Python 3.13, not removed). This weakness is in the resolution and analysis of dotted attribute-path names, and is distinct from and independently fixable from the module-origin trust weakness tracked as CVE-2026-16760: resolving or flagging dotted attribute-path imports closes this vector while leaving the module-level trust behavior unchanged. This bypass was verified to remain present on the vendor master branch at commit d011709 as of 2026-10-30, after the vendor's October blocklist additions and a new heuristic that flags private stdlib attributes; because the public class method Values.readfile is neither blocklisted nor flagged as a private attribute, it is not addressed by those remediations.