CVE-2026-29645

HIGH
MEDIUM Priority: 0.04 BB Relevance: 75/100
Published: 2026-04-20 Modified: 2026-11-11 First seen: 2026-11-11 Status: active

Attack Surface

Network Low Complexity No Auth No Interaction

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: None
S: Unchanged
C: None
I: None
A: High

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.

Weakness Classification (2)

Affected Software (1)

VendorProductVersion
xiangshan nemu 2025.12

Bug Bounty Relevance

75 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity
✓ No user interaction

CVSS Score

7.5 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploitation Probability

0.54%
Raw Score 0.005430
Percentile 46.2%
Date 2026-11-14

EPSS Trend

2026-11-14
0.00543
2026-11-13
0.00543
2026-11-12
0.00543
2026-11-10
0.00543

Intelligence Sources

nvd ref →