Stream: git-wasmtime

Topic: wasmtime / PR #12651 [42.0.0] Backport fixes for security...

Wasmtime GitHub notifications bot (Feb 24 2026 at 16:34):

alexcrichton opened PR #12651 from alexcrichton:back42 to bytecodealliance:ci/release-42.0.0:

This commit contains merged backports for two security advisories in Wasmtime:

• GHSA-852m-cvvp-9p4w
• GHSA-243v-98vx-264h

This introduces new knobs to Wasmtime to limit the scope of resources that WASI implementations will allocate on behalf of guests. Unlike backports to 41.0.x-and-prior these knobs all have default values which are considered reasonable for hosts if they don't further tune them. The following CLI knobs have been added:

• -Smax-resources - limits the total component-model resources a guest can allocate in a table
• -Shostcall-fuel - a broad limit which enforces that at most this amount of data will be copied from the guest to the host in any one API call (e.g. string values can't be too big, list<string> can't be quadratic, etc). This fuel is reset on each host function call.
• -Smax-random-size - the maximal size of the return value of the get-random-bytes and get-insecure-random-bytes WASI functions.
• -Smax-http-fields-size - a limit on the size of wasi:http fields values to avoid infinitely buffering data within the host.

The http crate has additionally been updated to avoid a panic when adding too many headers to a fields object.

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Wasmtime GitHub notifications bot (Feb 24 2026 at 16:34):

alexcrichton requested wasmtime-wasi-reviewers for a review on PR #12651.

Wasmtime GitHub notifications bot (Feb 24 2026 at 16:34):

alexcrichton requested pchickey for a review on PR #12651.

Wasmtime GitHub notifications bot (Feb 24 2026 at 16:34):

alexcrichton requested wasmtime-core-reviewers for a review on PR #12651.

Wasmtime GitHub notifications bot (Feb 24 2026 at 16:34):

alexcrichton requested wasmtime-default-reviewers for a review on PR #12651.

Wasmtime GitHub notifications bot (Feb 24 2026 at 16:40):

dicej submitted PR review.

Wasmtime GitHub notifications bot (Feb 24 2026 at 16:44):

alexcrichton updated PR #12651.

Wasmtime GitHub notifications bot (Feb 24 2026 at 16:47):

alexcrichton edited PR #12651.

Wasmtime GitHub notifications bot (Feb 24 2026 at 16:47):

alexcrichton closed without merge PR #12651.

Wasmtime GitHub notifications bot (Feb 24 2026 at 16:47):

alexcrichton reopened PR #12651 from alexcrichton:back42 to bytecodealliance:release-42.0.0.

Wasmtime GitHub notifications bot (Feb 24 2026 at 17:06):

alexcrichton updated PR #12651.

Wasmtime GitHub notifications bot (Feb 24 2026 at 17:51):

alexcrichton merged PR #12651.

Last updated: Mar 23 2026 at 16:19 UTC