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CVE-2026-29645 (GCVE-0-2026-29645)

Vulnerability from cvelistv5 – Published: 2026-04-20 00:00 – Updated: 2026-04-21 19:51
VLAI
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-21 13:33 UTC
CWE
  • n/a
  • CWE-131 - Incorrect Calculation of Buffer Size
  • CWE-1287 - Improper Validation of Specified Type of Input
Assigner
References
Show details on NVD website
To clipboard 

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