CVE-2026-115893

critical

Wasmtime is a runtime for WebAssembly.

Wasmtime is a runtime for WebAssembly. Prior to 36.0.19, 48.0.7, and 49.0.4, the Cranelift compiler backend on aarch64 can compile a Wasm br_table instruction with more than approximately 256,000 targets so that it has an incorrect conditional branch target. The branch can then jump to arbitrary other code at a user-controlled offset, allowing a user-controlled Wasm module to escape the sandbox on aarch64 engines using the default Cranelift backend. This issue is fixed in versions 36.0.19, 48.0.7, and 49.0.4.

CVSS

9.9

9.9 (CVSS v3.1)

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Severity source: NVD CVSS v3.1 (security-advisories@github.com)

Timeline (UTC)

Published: 2026-10-23 22:16

Modified: 2026-10-23 22:16

NVD status: Deferred

Last synced 2 days ago

Verified against the source API 2026-10-27 07:06 UTC

Exploitation

Not listed in CISA KEV (as of last catalog sync)

Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

Not reported by the source (unknown — not "none").

Weakness classification (CWE)

CWE-691

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

No vendor advisory or patch reference tagged by NVD. Check the references below.

References

https://github.com/bytecodealliance/wasmtime/commit/222ff3a65dab9aa7011f8c246937751a0bac5a... security-advisories@github.com
https://github.com/bytecodealliance/wasmtime/commit/994549891c8a706cb4f2809f9d17b9f67b31e6... security-advisories@github.com
https://github.com/bytecodealliance/wasmtime/commit/e61df1b454be9313d61a5f8de07722a421139b... security-advisories@github.com
https://github.com/bytecodealliance/wasmtime/commit/f517bd6e890c7c1291ab9fe05d8cc0c9f11e56... security-advisories@github.com
https://github.com/bytecodealliance/wasmtime/pull/14818 security-advisories@github.com
https://github.com/bytecodealliance/wasmtime/pull/14819 security-advisories@github.com
https://github.com/bytecodealliance/wasmtime/pull/14820 security-advisories@github.com
https://github.com/bytecodealliance/wasmtime/pull/14826 security-advisories@github.com
https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.19 security-advisories@github.com
https://github.com/bytecodealliance/wasmtime/releases/tag/v48.0.7 security-advisories@github.com
https://github.com/bytecodealliance/wasmtime/releases/tag/v49.0.4 security-advisories@github.com
https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-mghf-wjfp-p5xm security-advisories@github.com

Data sources

NVD CVE API 2.0 — fetched 2026-10-27 07:06 UTC · record ↗

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