zwesty
Write-ups / Day 19 / Script
Day 19 · Mon, Oct 19 · Script

Sharp Practice

Prey slaughtered

Multi-language script analysis, ATT&CK mapping

STTMClaude Homebase Both

Flags are shortened to their first 8 and last 4 characters because they're unique per team.

Challenge ID
script-analysis-day-19-managed-assembly-bridge (+ /time_trial, /mastery)
Solved
2026-10-19, all three modes, by 09:01:11 ET
Player
Zwesty (solo); solved by our automated morning solver (a scheduled script on our Kali VM), built with Claude Code (Opus 5.5)

The challenge

Every earlier day's script fields plus a new host: C# script (.csx), 1,249 questions on the Single Solve. Written from the solver's report and the start reply's question list; the specimens weren't reopened.

Safety

Script specimens are hostile: static analysis only, on our Kali VM. No excerpts quoted.

The modes

  • Single Solve: a core batch of 1,120 answers was accepted, then one merged batch of 129 from the solver's add-on readers → CORRECT at 09:00:51.
Single Solve   CORRECT 09:00:51
Time Trial     CORRECT 09:01:01  flag fea902fb…b53f   solve 90 ms,  submit +3.24 s
Mastery        CORRECT 09:01:11  flag baf7b584…306b   solve 431 ms, submit +4.06 s

Time to solve

All three modes were solved by 09:01:11 ET, 71 seconds after release, the first lane of the day done.

Takeaways

  • Yesterday's fix held: the split-header reader built for Day 18 and hardened overnight carried a new host language with no change, so Script finished 71 seconds after release, the first lane done.