Sweep 19 Sep 2026 · 02:36Z Build v2.1.278 500 read Stable v2.1.267 Latest v2.1.278 Next v2.1.278 Feeds RSS JSON llms.txt Unofficial
Claude Code v2.1.271 ·

Env-var sanitization for spawned processes reworked

Environment variables passed to spawned processes are filtered more thoroughly

TierUnder the hoodhow much it should matter to you
Useful1my rating, 1 to 5
Signal1worth watching, 1 to 5
AreaElsewherewhat it touches
KindInternal Changesin v2.1.271,
Under the hood

Environment variables passed to spawned processes are filtered more thoroughly

What

When Claude Code builds the environment variables for a process it spawns, it now runs an extra filtering pass over variable names that contain a dash, checking them against a lookup that ignores hyphen differences. It also pulls in additional sources of variables to exclude, beyond the fixed list it used before.

Why

This broadens and tightens which environment variables get passed through to spawned processes, reducing the chance that an unwanted or sensitive variable leaks into a child process.

How sure we are
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubtThe finding does not say which variables or sources are newly excluded, so the practical effect on any specific variable is unclear.

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