[renovate]

This PR contains the following updates:

Package	Type	Update	Change
wasmtime	workspace.dependencies	patch	49.0.2 → 49.0.4

---

Wasmtime: Panic lowering a host-created component model stream into a guest that expects a different payload type

CVE-2026-115892 / GHSA-9pvw-hwfg-92h5

More information

Details

Summary

Wasmtime may panic when the host lowers a component model stream or future into a guest, if the host created that stream or future with one payload type and the guest expects a different one. This can happen when an embedder creates a stream or future, passes it through a guest, receives it back under a type-erased type such as StreamAny or FutureAny, and then passes it to a guest function with a different payload type.

GHSA-63h4-6cx9-pjfj is a related advisory also fixing issues within this area, and this advisory is being issued for portions of Wasmtime that were not fixed as part of that advisory.

Impact

This affects embedders that do all of the following:

1. Create streams or futures on the host with StreamReader::new or FutureReader::new
2. Pass them to guest code and receive them back as StreamAny, FutureAny, Val::Stream/Val::Future, or a typed reader whose payload is one of these.
3. Pass them on to a guest function whose stream or future payload type differs from the type the host created them with.

A guest can cause the mismatch in step 3 when it controls the types of the functions it exports or of the values it returns. In that case a malicious guest can make the host panic, a denial of service. Embedders that only use statically typed StreamReader<T>/FutureReader<T> with concrete payload types throughout, or that never pass streams or futures they created through a guest and back, are not affected.

Severity

• CVSS Score: 5.7 / 10 (Medium)
• Vector String: CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

References

• https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-9pvw-hwfg-92h5
• https://github.com/bytecodealliance/wasmtime/pull/14819
• https://github.com/bytecodealliance/wasmtime/pull/14820
• https://github.com/bytecodealliance/wasmtime/pull/14827
• https://github.com/bytecodealliance/wasmtime/commit/222ff3a65dab9aa7011f8c246937751a0bac5abd
• https://github.com/bytecodealliance/wasmtime/commit/48dacc76241f06088e79f3ce1b17642f2f7bf158
• https://github.com/bytecodealliance/wasmtime/commit/994549891c8a706cb4f2809f9d17b9f67b31e618
• https://github.com/bytecodealliance/wasmtime/releases/tag/v48.0.7
• https://github.com/bytecodealliance/wasmtime/releases/tag/v49.0.4
• https://rustsec.org/advisories/RUSTSEC-2026-0378.html
• https://github.com/advisories/GHSA-9pvw-hwfg-92h5

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

---

Wasmtime: Cranelift backend on aarch64 can jump to incorrect target on large Wasm br_table instruction

CVE-2026-115893 / GHSA-mghf-wjfp-p5xm

More information

Details

Summary

When running with the Cranelift compiler backend on an aarch64 target, Wasmtime can compile a Wasm module with more than ~256k targets on one br_table instruction in a way that results in an incorrect conditional branch target. This conditional branch could then jump to arbitrary other code (at an user-controlled offset), leading to arbitrary sandbox escapes.

Impact

Any Wasmtime engine running on aarch64 with default settings can be forced to jump to arbitrary code by a user-controlled Wasm module. All versions of Wasmtime/Cranelift that support aarch64, since the initial release of that support in 2020 (before Wasmtime v1.0), are affected.

Patches

Wasmtime v36.0.19, v48.0.7, and v49.0.4 have been released which all fix this issue.

Severity

• CVSS Score: 9.9 / 10 (Critical)
• Vector String: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

References

• https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-mghf-wjfp-p5xm
• https://nvd.nist.gov/vuln/detail/CVE-2026-115893
• https://github.com/bytecodealliance/wasmtime/pull/14818
• https://github.com/bytecodealliance/wasmtime/pull/14819
• https://github.com/bytecodealliance/wasmtime/pull/14820
• https://github.com/bytecodealliance/wasmtime/pull/14826
• https://github.com/bytecodealliance/wasmtime/commit/222ff3a65dab9aa7011f8c246937751a0bac5abd
• https://github.com/bytecodealliance/wasmtime/commit/994549891c8a706cb4f2809f9d17b9f67b31e618
• https://github.com/bytecodealliance/wasmtime/commit/e61df1b454be9313d61a5f8de07722a421139bbe
• https://github.com/bytecodealliance/wasmtime/commit/f517bd6e890c7c1291ab9fe05d8cc0c9f11e56aa
• https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.19
• https://github.com/bytecodealliance/wasmtime/releases/tag/v48.0.7
• https://github.com/bytecodealliance/wasmtime/releases/tag/v49.0.4
• https://rustsec.org/advisories/RUSTSEC-2026-0379.html
• https://github.com/advisories/GHSA-mghf-wjfp-p5xm

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

---

Release Notes

bytecodealliance/wasmtime (wasmtime)

v49.0.4

Compare Source

49.0.4

Released 2026-10-19.

Fixed

• wasi-http: Guests can add conflicting content lengths to messages
  GHSA-r8xh-cgf7-392j
• wasi-http p3: forwarded trailers aren't checked against is_forbidden_header hook
  GHSA-jxcf-8qw5-5c33
• wasi-http p3: Guests can set incorrect content-length for spliced response bodies
  GHSA-9prg-84vf-g5fc
• Cranelift backend on aarch64 can jump to incorrect target on large Wasm br_table instruction
  GHSA-mghf-wjfp-p5xm
• Update rustls to 0.23.46
  #​14767
• Panic lowering a host-created component model stream into a guest that expects a different payload type.
  GHSA-9pvw-hwfg-92h5

v49.0.3

Compare Source

49.0.3

Released 2026-10-14.

Fixed

• Out-of-bounds zero-length stream writes can panic.
  GHSA-93g3-36p8-x2gc

• Host panic when component call_async is cancelled under some conditions.
  GHSA-3r89-v5mq-j5xf

• Panic on erroneous call-to-host from guest realloc call.
  GHSA-7v24-42x9-pxf7

• Yielding in a component start function can lead to a host panic.
  GHSA-5hhx-4wrr-3j9g

• Panic when invoking an async-lifted function via call.
  GHSA-m6w2-jwq2-cv2c

• Panic when pending calls are run after a trap.
  GHSA-hmwq-g22x-qjw5

• Stack overflow dropping a long chain of recursive types.
  GHSA-wjc8-633q-pwxr

• Wasmtime may not properly enforce async-entrypoint requirement.
  GHSA-vcg5-q8m5-8379

• Panic viewing component model stream or future as the wrong type.
  GHSA-63h4-6cx9-pjfj

• Component-model handle tables are capped only per instance and charged to no
  limit.
  GHSA-q554-3cjc-rx7p

• Exception tags can cause host data structures to be unaligned.
  GHSA-p79w-pv2r-29qp

• Filesystem sandbox escape when renaming symlinks with trailing slashes.
  GHSA-m9f7-9w4p-gv38

• Overlapping string transcode in a fused adapter can panic.
  GHSA-54p9-vhhq-8f7q

• Guests can send absolute-form HTTP requests to different hosts.
  GHSA-5qpp-g3j2-8frx

• wasi-http: Request with long url before query parameter crashes host.
  GHSA-w36r-2hch-9xp9

---

Configuration

📅 Schedule: (in timezone Asia/Tokyo)

• Branch creation
  • At any time (no schedule defined)
• Automerge
  • At any time (no schedule defined)

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

---

• If you want to rebase/retry this PR, check this box

---

This PR was generated by Mend Renovate. View the repository job log.