CVE-2026-29645
Last modified
CVE-2026-29645 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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. EPSS estimates a 0.54% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions | Update |
|---|---|---|---|
| Xiangshan | Nemu | 2025.12 | R1 |
References
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2026-29645?
How severe is CVE-2026-29645?
How do I fix CVE-2026-29645?
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2026
- CVE-2026-29628A stack overflow in the experimental/tinyobj_loader_opt.h fi…6.2
- CVE-2026-2963A vulnerability was determined in Jinher OA C6 up to 2026021…6.3
- CVE-2026-2964A vulnerability was identified in higuma web-audio-recorder-…9.8
- CVE-2026-29642A local attacker who can execute privileged CSR operations (…7.8
- CVE-2026-29643XiangShan (Open-source high-performance RISC-V processor) co…7.1
- CVE-2026-29644XiangShan (open-source high-performance RISC-V processor) co…5.3
- CVE-2026-29646In OpenXiangShan NEMU prior to 55295c4, when running with RV…9.8
- CVE-2026-29647In OpenXiangShan NEMU, insufficient Smstateen permission enf…6.5
- CVE-2026-29648In OpenXiangShan NEMU, when Smstateen is enabled, clearing m…8.8
- CVE-2026-29649NEMU contains an implementation flaw in its RISC-V Hyperviso…9.8
- CVE-2026-2965A security flaw has been discovered in 07FLYCMS, 07FLY-CMS a…2.4
- CVE-2026-2966A weakness has been identified in Cesanta Mongoose up to 7.2…3.7
Are you affected by CVE-2026-29645?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST
