NEMU contains an implementation flaw in its RISC-V Hypervisor CSR handling where henvcfg[7:4] (CBIE/CBCFE/CBZE-related fields) is incorrectly masked/updated based on menvcfg[7:4], so a machine-mode write to menvcfg can implicitly modify the hypervisor's environment configuration. This can lead to incorrect enforcement of virtualization configuration and may cause unexpected traps or denial of service when executing cache-block management instructions in virtualized contexts (V=1).
References
| Link | Resource |
|---|---|
| https://docs.riscv.org/reference/isa/priv/hypervisor.html | Product |
| https://docs.riscv.org/reference/isa/priv/machine.html | Product |
| https://github.com/OpenXiangShan/NEMU/issues/681 | Issue Tracking |
| https://github.com/OpenXiangShan/NEMU/pull/689 | Issue Tracking Patch |
Configurations
History
24 Apr 2026, 19:23
| Type | Values Removed | Values Added |
|---|---|---|
| CPE | cpe:2.3:a:xiangshan:nemu:-:*:*:*:*:*:*:* | |
| References | () https://docs.riscv.org/reference/isa/priv/hypervisor.html - Product | |
| References | () https://docs.riscv.org/reference/isa/priv/machine.html - Product | |
| References | () https://github.com/OpenXiangShan/NEMU/issues/681 - Issue Tracking | |
| References | () https://github.com/OpenXiangShan/NEMU/pull/689 - Issue Tracking, Patch | |
| First Time |
Xiangshan nemu
Xiangshan |
21 Apr 2026, 20:16
| Type | Values Removed | Values Added |
|---|---|---|
| CWE | CWE-693 | |
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 9.8 |
20 Apr 2026, 20:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-04-20 20:16
Updated : 2026-04-24 19:23
NVD link : CVE-2026-29649
Mitre link : CVE-2026-29649
CVE.ORG link : CVE-2026-29649
JSON object : View
Products Affected
xiangshan
- nemu
CWE
CWE-693
Protection Mechanism Failure