WebAssembly Micro Runtime (WAMR) is a lightweight standalone WebAssembly (Wasm) runtime. Prior to 2.4.5, wasi_poll_oneoff in core/iwasm/libraries/libc-wasi/libc_wasi_wrapper.c validates the output pointer for only one wasi_event_t, while wasmtime_ssp_poll_oneoff in core/iwasm/libraries/libc-wasi/sandboxed-system-primitives/src/posix.c can write as many events as the guest-controlled nsubscriptions value. A crafted guest module can provide multiple subscriptions that produce events while positioning an output region large enough for only one event, causing a later out[nevents] write to cross the validated Wasm linear-memory boundary into adjacent host heap memory. The overwrite contains partly attacker-controlled event data and can reliably crash the host process, with further confidentiality or integrity consequences depending on heap layout. This issue is fixed in version 2.4.5.
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Fri, 06 Nov 2026 17:00:00 +0000
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Bytecodealliance
Bytecodealliance wasm-micro-runtime |
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Bytecodealliance
Bytecodealliance wasm-micro-runtime |
Thu, 05 Nov 2026 17:45:00 +0000
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| Description | WebAssembly Micro Runtime (WAMR) is a lightweight standalone WebAssembly (Wasm) runtime. Prior to 2.4.5, wasi_poll_oneoff in core/iwasm/libraries/libc-wasi/libc_wasi_wrapper.c validates the output pointer for only one wasi_event_t, while wasmtime_ssp_poll_oneoff in core/iwasm/libraries/libc-wasi/sandboxed-system-primitives/src/posix.c can write as many events as the guest-controlled nsubscriptions value. A crafted guest module can provide multiple subscriptions that produce events while positioning an output region large enough for only one event, causing a later out[nevents] write to cross the validated Wasm linear-memory boundary into adjacent host heap memory. The overwrite contains partly attacker-controlled event data and can reliably crash the host process, with further confidentiality or integrity consequences depending on heap layout. This issue is fixed in version 2.4.5. | |
| Title | WebAssembly Micro Runtime: Heap Buffer Overflow in WAMR WASI poll_oneoff Output Buffer | |
| Weaknesses | CWE-122 | |
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cvssV4_0
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Status: PUBLISHED
Assigner: GitHub_M
Published: 2026-11-05T17:27:16.493Z
Updated: 2026-11-09T17:45:52.068Z
Reserved: 2026-06-16T13:49:33.556Z
Link: CVE-2026-54914
No data.
Status : Received
Published: 2026-11-05T18:17:08.873
Modified: 2026-11-09T18:17:29.387
Link: CVE-2026-54914
No data.