PMA state tampering via illegal CSR shadow writes
Published Apr 21, 2026 · Updated Apr 21, 2026
Improper access control in XiangShan's NewCSR module allows local users to alter custom PMA CSR state through illegal CSR writes. The distributed write-enable path forwards a legal-write signal to replicated PMA registers without also blocking an illegal CSR address. Code execution on the core is required, and the consequence depends on how the integrated platform uses PMA for security and isolation.
Summary
What happened
Improper access control in XiangShan's NewCSR module allows local users to alter custom PMA CSR state through illegal CSR writes. The distributed write-enable path forwards a legal-write signal to replicated PMA registers without also blocking an illegal CSR address. Code execution on the core is required, and the consequence depends on how the integrated platform uses PMA for security and isolation.
The record
- CVE
- CVE-2026-29644
- Published
- Apr 21, 2026
- Updated
- Apr 21, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-284, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Apr 21, 2026CVE publishedPublication date reported by the CVE source.
- Apr 21, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
- ill-test.zip illegal-instruction reproducerproof of concept · unverified
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Technologies
Your stack
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Your stack
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