CVE-2026-29642
XiangShan RISC-V Firmware WPRI Bit Manipulation Vulnerability
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.
INFO
Published Date :
April 20, 2026, 9:16 p.m.
Last Modified :
April 20, 2026, 9:16 p.m.
Remotely Exploit :
No
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-29642
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Update XiangShan to a version after commit aecf601e803bfd2371667a3fb60bfcd83c333027.
- Review and reconfigure CSR settings if compromised.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-29642.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-29642 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-29642
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-29642 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-29642 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Apr. 20, 2026
Action Type Old Value New Value 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. Added Reference https://docs.riscv.org/reference/isa/priv/machine.html Added Reference https://docs.riscv.org/reference/isa/priv/priv-csrs.html Added Reference https://github.com/OpenXiangShan/XiangShan/commit/5e3dd63 Added Reference https://github.com/OpenXiangShan/XiangShan/issues/3934