CVE-2026-29642

OVERVIEW CVE-2026-29642 is a local privilege escalation vulnerability affecting XiangShan RISC-V processor implementations. The flaw allows attackers with privileged execution capabilities to manipulate menvcfg (machine environment configuration) register operations in a way that unexpectedly sets reserved WPRI bits in the xstatus register to 1, violating RISC-V specifications that require reserved fields to remain unmodified during legitimate software operations. SEVERITY This vulnerability carries a CVSS 3.1 score of 7.8 (HIGH) with a local attack vector requiring low complexity and low privileges. The attack requires no user interaction and impacts system confidentiality, integrity, and availability. An attacker who can execute privileged CSR (Control and Status Register) operations or induce firmware to perform them could potentially achieve unauthorized information disclosure, system modification, or denial of service. The FAUCET Risk Score of 48.0 reflects moderate organizational concern. EXPLOITATION STATUS Currently, CVE-2026-29642 shows no evidence of active exploitation in the wild. It does not appear on CISA's Known Exploited Vulnerabilities (KEV) catalog and is marked as inactive on exploit tracking lists. The EPSS score of 0.000110 indicates minimal probability of exploitation in real-world scenarios. No public exploit code is documented, though the technical description provides sufficient detail for potential weaponization by sophisticated threat actors familiar with RISC-V architecture.