Strip bare control characters from CSP report terminal output - #1405
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_sanitize_terminal() only removed ESC-prefixed ANSI sequences, so bare C0 controls (CR, LF, BS, BEL, ...), DEL, C1 controls (e.g. 0x9B 8-bit CSI) and a stray ESC in unauthenticated /__csp__ report fields reached the operator's terminal, allowing log lines to be overwritten or forged. Strip all remaining control characters and Unicode bidi overrides after the ANSI escape pass. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_019b8mWRK1bS7PUszC6SQKGB
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_sanitize_terminal()only removed ESC-prefixed ANSI sequences. Bare control characters in the unauthenticated/__csp__report fields were still printed to the operator's terminal, so an attacker could overwrite or forge log lines. This covers:0x9B(8-bit CSI)Changes
_sanitize_terminal()now also strips all remaining C0, DEL and C1 control characters, plus Unicode bidi override characters (U+200E/F, U+202A–202E, U+2066–2069). Ordinary non-ASCII text is kept.ruff formatcan't rewrite the escapes into invisible literal characters in the source.Tests
/__csp__test uses CR and LF injection payloads.mesop/serverpass, andruff check/ruff format --check(v0.5.4) pass.Reported by zx (@manus-pi).
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https://claude.ai/code/session_019b8mWRK1bS7PUszC6SQKGB
Generated by Claude Code