{"cve":"CVE-2025-56301","nvd":{"published":"2025-09-30T15:15:52.040","modified":"2026-06-17T09:42:30.723","status":"Analyzed","description":"An issue was discovered in Chipsalliance Rocket-Chip commit f517abbf41abb65cea37421d3559f9739efd00a9 (2025-01-29) allowing attackers to corrupt exception handling and privilege state transitions via a flawed interaction between exception handling and MRET return mechanisms in the CSR logic when an exception is triggered during MRET execution. The Control and Status Register (CSR) logic has a flawed interaction between exception handling and exception return (MRET) mechanisms which can cause faulty trap behavior. When the MRET instruction is executed in machine mode without being in an exception state, an Instruction Access Fault may be triggered. This results in both the exception handling logic and the exception return logic activating simultaneously, leading to conflicting updates to the control and status registers.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-1281"],"references":["https://github.com/chipsalliance/rocket-chip","https://github.com/chipsalliance/rocket-chip/blob/f517abbf41abb65cea37421d3559f9739efd00a9/src/main/scala/rocket/CSR.scala","https://github.com/chipsalliance/rocket-chip/blob/master/src/main/scala/rocket/CSR.scala","https://github.com/heyfenny/Vulnerability_disclosure/blob/main/RISCV/Rocket-chip/CVE-2025-56301/details.md","https://lf-riscv.atlassian.net/wiki/spaces/HOME/pages/16154769/RISC-V+Technical+Specifications#ISA-Specifications"],"products":["chipsalliance:rocket-chip"],"source":"nvd","synced_at":"2026-10-19T22:11:26.888974865+00:00"},"epss":{"cve":"CVE-2025-56301","score":0.00641,"percentile":0.50705,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}