CVE-2025-58749: WAMR runtime hangs or crashes with large memory.fill addresses in LLVM-JIT mode

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2025-09-16 · updated 2026-06-17
Weakness: CWE-190

Description

WebAssembly Micro Runtime (WAMR) is a lightweight standalone WebAssembly (Wasm) runtime. In WAMR versions prior to 2.4.2, when running in LLVM-JIT mode, the runtime cannot exit normally when executing WebAssembly programs containing a memory.fill instruction where the first operand (memory address pointer) is greater than or equal to 2147483648 bytes (2GiB). This causes the runtime to hang in release builds or crash in debug builds due to accessing an invalid pointer. The issue does not occur in FAST-JIT mode or other runtime tools. This has been fixed in version 2.4.2.

Affected products

bytecodealliance wasm-micro-runtime: before 2.4.2 — fixed in 2.4.2

How to fix

Upgrade to a fixed version: bytecodealliance wasm-micro-runtime 2.4.2. Check the vendor advisory for mitigations.

References

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