---
id: CVE-2026-55894
title: Capstone is a disassembly framework
summary: >-
  Capstone is a disassembly framework. In 6.0.0-Alpha9 and earlier, Capstone's
  arch/SH/SHDisassembler.c sh_disassemble() function computes an idx value from
  a raw 16-bit instruction without ensuring it is within the active
  mode-specific de…
severity: none
cwe:
  - CWE-125
published: '2026-08-20'
updated: '2026-09-18'
sourceUpdated: '2026-09-18T20:09:01.757'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-55894'
references:
  - url: >-
      https://github.com/capstone-engine/capstone/commit/09e76802380b9e94d9720c44458d9d5282219e7e
    label: security-advisories@github.com
  - url: >-
      https://github.com/capstone-engine/capstone/commit/e17ee44a8307ea33375b4727ac4f987650bf7bed
    label: security-advisories@github.com
  - url: 'https://github.com/capstone-engine/capstone/pull/2968'
    label: security-advisories@github.com
  - url: 'https://github.com/capstone-engine/capstone/pull/2969'
    label: security-advisories@github.com
  - url: 'https://github.com/capstone-engine/capstone/releases/tag/6.0.0-Alpha10'
    label: security-advisories@github.com
  - url: >-
      https://github.com/capstone-engine/capstone/security/advisories/GHSA-gf2c-xwcp-hvf4
    label: security-advisories@github.com
  - url: >-
      https://github.com/capstone-engine/capstone/security/advisories/GHSA-gf2c-xwcp-hvf4
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
epss: 0.00194
epssPercentile: 0.08006
ingestedAt: '2026-09-18T20:51:25.650Z'
---

## Overview

Capstone is a disassembly framework. In 6.0.0-Alpha9 and earlier, Capstone's arch/SH/SHDisassembler.c sh_disassemble() function computes an idx value from a raw 16-bit instruction without ensuring it is within the active mode-specific decode[] function-pointer table. An application using CS_ARCH_SH with CS_MODE_SH2A or CS_MODE_SH4A and CS_MODE_SHFPU can pass crafted bytecode through cs_disasm_iter() or cs_disasm(), causing the decode[idx] test to read outside the table and terminate the process with a segmentation fault. No code execution or information disclosure was demonstrated. This issue is fixed in version 6.0.0-Alpha10.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.