CVE-2026-115893
Wasmtime: Cranelift backend on aarch64 can jump to incorrect target on large Wasm `br_table` instruction
Description
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.
INFO
Published Date :
Oct. 23, 2026, 10:16 p.m.
Last Modified :
Oct. 23, 2026, 10:16 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | MITRE-CVE | ||||
| CVSS 3.1 | CRITICAL | [email protected] |
Solution
- Update Wasmtime to version 36.0.19 or later.
- Update Wasmtime to version 48.0.7 or later.
- Update Wasmtime to version 49.0.4 or later.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-115893.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-115893 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-115893
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-115893 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-115893 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by [email protected]
Oct. 23, 2026
Action Type Old Value New Value Added Description 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. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H Added CWE CWE-691 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/115xxx/CVE-2026-115893.json">CVE-2026-115893</a> Added Reference https://github.com/bytecodealliance/wasmtime/commit/222ff3a65dab9aa7011f8c246937751a0bac5abd Added Reference https://github.com/bytecodealliance/wasmtime/commit/994549891c8a706cb4f2809f9d17b9f67b31e618 Added Reference https://github.com/bytecodealliance/wasmtime/commit/e61df1b454be9313d61a5f8de07722a421139bbe Added Reference https://github.com/bytecodealliance/wasmtime/commit/f517bd6e890c7c1291ab9fe05d8cc0c9f11e56aa Added Reference https://github.com/bytecodealliance/wasmtime/pull/14818 Added Reference https://github.com/bytecodealliance/wasmtime/pull/14819 Added Reference https://github.com/bytecodealliance/wasmtime/pull/14820 Added Reference https://github.com/bytecodealliance/wasmtime/pull/14826 Added Reference https://github.com/bytecodealliance/wasmtime/releases/tag/v36.0.19 Added Reference https://github.com/bytecodealliance/wasmtime/releases/tag/v48.0.7 Added Reference https://github.com/bytecodealliance/wasmtime/releases/tag/v49.0.4 Added Reference https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-mghf-wjfp-p5xm