F5, a Seattle-based maker of networking software, disclosed the breach on Wednesday. Wednesday’s disclosure went on to say the threat group downloaded proprietary BIG-IP source code information about vulnerabilities that had been privately discovered but not yet patched. The hackers also obtained configuration settings that some customers used inside their networks. F5 said that investigations by two outside intrusion-response firms have yet to find any evidence of supply-chain attacks. Two days ago, F5 rotated BIG-IP signing certificates, though there was no immediate confirmation that the move is in response to the breach.