A local attacker who can execute privileged CSR operations (or can induce firmware to do so) performs carefully crafted reads/writes to menvcfg (e.g., csrrs in M-mode). On affected XiangShan versions (commit aecf601e803bfd2371667a3fb60bfcd83c333027, 2024-11-19), these menvcfg accesses can unexpectedly set WPRI (reserved) bits in the status view (xstatus) to 1. RISC-V defines WPRI fields as "writes preserve values, reads ignore values," i.e., they must not be modified by software manipulating other fields, and menvcfg itself contains multiple WPRI fields.
History

Mon, 20 Apr 2026 21:00:00 +0000

Type Values Removed Values Added
Description A local attacker who can execute privileged CSR operations (or can induce firmware to do so) performs carefully crafted reads/writes to menvcfg (e.g., csrrs in M-mode). On affected XiangShan versions (commit aecf601e803bfd2371667a3fb60bfcd83c333027, 2024-11-19), these menvcfg accesses can unexpectedly set WPRI (reserved) bits in the status view (xstatus) to 1. RISC-V defines WPRI fields as "writes preserve values, reads ignore values," i.e., they must not be modified by software manipulating other fields, and menvcfg itself contains multiple WPRI fields.
References

cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published:

Updated: 2026-04-20T20:30:19.577Z

Reserved: 2026-03-04T00:00:00.000Z

Link: CVE-2026-29642

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-04-20T21:16:19.393

Modified: 2026-04-20T21:16:19.393

Link: CVE-2026-29642

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.