CVE-2026-29645_CVE-2026-29645

7.5 / 10

HIGH

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

Description

NEMU (OpenXiangShan/NEMU) before v2025.12.r2 contains an improper instruction-validation flaw in its RISC-V Vector (RVV) decoder. The decoder does not correctly validate the funct3 field when decoding vsetvli/vsetivli/vsetvl, allowing certain invalid OP-V instruction encodings to be misinterpreted and executed as vset* configuration instructions rather than raising an illegal-instruction exception. This can be exploited by providing crafted RISC-V binaries to cause incorrect trap behavior, architectural state corruption/divergence, and potential denial of service in systems that rely on NEMU for correct execution or sandboxing.

Basic Information

ID CVE-2026-29645

Source mitre

Published Apr 20, 2026 at 00:00

Modified Apr 21, 2026 at 19:51

Affected Product

Vendor n/a

Product n/a

Version n/a

Affected Versions n/a n/a n/a

CWE Classification

CWE-131 CWE-1287

References

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    "published": "2026-04-20T00:00:00.000Z",
    "modified": "2026-04-21T19:51:06.424Z",
    "type": "cve",
    "title": "CVE-2026-29645",
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    "references": "https://github.com/OpenXiangShan/NEMU/issues/952\nhttps://github.com/OpenXiangShan/NEMU/pull/958\nhttps://github.com/OpenXiangShan/NEMU/commit/481de637d5fc5838356caee80a79e56a33754039\nhttps://docs.riscv.org/reference/isa/unpriv/v-st-ext.html",
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