[Bug][cyber] HMAC authentication code development blocked by overly-broad crypto classifier (req_011CcowZRmLbN6rxggQDi5ei)

Triage: kind cyber · domain general · severity session-halted (blocked authorized work) · reproducible: yes — server-side via the Request ID(s) below

Type: Cybersecurity safety-filter false positive · Work domain (heuristic): general

Why this is a false positive

Standard HMAC-SHA256 authentication implementation in a mainstream language is being incorrectly flagged as a cybersecurity threat, preventing legitimate code compilation, editing, and documentation updates. The safety classifier appears to conflate routine application development activities involving cryptographic libraries with actual malicious activity.

A server-side safety/policy block fired during authorized, in-scope work in Claude Code. Filing as a false positive. Recurred 1× across 1 session(s); first seen 2026-07-08T04:15:31.687Z.

Request IDs (lookup-able server-side)

• req_011CcowZRmLbN6rxggQDi5ei (2026-07-08T04:15:31.687Z)

In-scope justification

False positive — in-scope, authorized security work; not out of scope. Filed automatically by claudit.

Block message

API Error: Opus 4.8 has safety measures that flagged this message for a cybersecurity topic. To learn about the Cyber Verification Program and apply for access, visit our help center: https://[REDACTED]/en/articles/14604842-real-time-cyber-safeguards-on-claude.

If you were not engaging in a cybersecurity topic, please send feedback via /feedback.

Request ID: req_011CcowZRmLbN6rxggQDi5ei

Environment: Claude Code, Linux. · Work domain: general

Related reports (same work session, linked)

Distinct false-positive blocks from the same work session, each its own report:
#75503, #75504, #75506, #75519, #75536, #75539

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_{🔎 Filed automatically by ClAudit v2.0.110 — a FOSS tool for reporting false-positive Claude Code blocks.}