Cryptanalysis of branching program obfuscators, Yilei Chen and Craig Gentry and Shai Halevi https://eprint.iacr.org/2016/998 Proof-of-concept implimentation of the 3-step attack on GGHRSW based on GGH13.
More attacks on GGH15-based obfuscators, Yilei Chen and Vinod Vaikuntanathan and Hoeteck Wee https://eprint.iacr.org/2018/360 Proof-of-concept implimentation of the rank attack on GGHRSW based on GGH15.