CVE-2021-1104: Risc-V Instruction Set Manual

Critical severity, CVSS 9.8. EPSS: 1.7% chance of exploitation in the next 30 days.

The RISC-V Instruction Set Manual contains a documented ambiguity for the Machine Trap Vector Base Address (MTVEC) register that may lead to a vulnerability due to the initial state of the register not being defined, potentially leading to information disclosure, data tampering and denial of service.

Affected products

• Risc-V Instruction Set Manual: any version

Published 2021-08-13. Last modified 2026-06-17.