Agent security needs executable proof
MOSAIC-Bench gives the clearest security signal. It splits each malicious objective across three ordinary engineering tickets, then checks the final application with deterministic proof-of-concept oracles in Docker. Across nine production coding agents, staged tickets produced attack success rates of 53.3% to 85.9%, with only two refusals across the benchmark. Reviewer agents also missed confirmed-vulnerable cumulative diffs: neutral review approved 24.8% as routine pull requests.
PoVSmith takes the defensive side of the same problem. It asks a coding agent to find application entry points that reach vulnerable library APIs, write JUnit proof-of-vulnerability tests, repair them with build feedback, and judge the execution logs. On 33 Java application-library pairs, it found 152 correct call paths, compiled 141 generated tests, and triggered vulnerabilities in 84 cases.