AIKIDO-2026-860430

TL;DR

The symbolic-cfi crate converts call frame information from object files into Breakpad ASCII format, including for Windows PE binaries. When processing a PE, AsciiCfiWriter follows the chained UNWIND_INFO list for each function without bounding how many links it traverses. A malformed or adversarial PE whose unwind info forms a self-referential or excessively long chain causes the writer to loop without terminating, pinning CPU and hanging the processing thread. The fix adds a configurable maximum chain length and returns a new ExceededUnwindChainLength error when the limit is exceeded.