"In recent cybersecurity tests of major weapon systems DOD is developing, testers playing the role of the adversary were able to take control of systems relatively easily and operate largely undetected," a press release summarizing the audit’s conclusions stated.
Hackers were able to take control of systems and operate the weapons undetected by using "relatively simple tools and techniques," the report said.
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The release explained that until relatively recently, the Defense Department did not make weapon cybersecurity a priority — a deficiency that weapons developers had only recently begun to correct.
The GAO report also warned vulnerabilities uncovered in recent tests likely to represent a fraction of total vulnerabilities due to testing limitations, the report said.