---
id: CVE-2026-55893
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 floating-point decoders such as opFADD, opFMUL,
  and opFSUB call set_reg() and set_reg_n() using sh_info.op.op_count without
  checking…
severity: none
cwe:
  - CWE-122
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-2026-55893'
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-3hpv-wr3j-rxwh
    label: security-advisories@github.com
tags:
  - nvd
epss: 0.0014
epssPercentile: 0.03738
ingestedAt: '2026-09-18T20:51:25.649Z'
---

## Overview

Capstone is a disassembly framework. In 6.0.0-Alpha9 and earlier, Capstone's arch/SH/SHDisassembler.c SH floating-point decoders such as opFADD, opFMUL, and opFSUB call set_reg() and set_reg_n() using sh_info.op.op_count without checking the fixed-size operands[] array. Repeated crafted instructions processed through cs_disasm_iter() or cs_disasm() with CS_ARCH_SH, CS_MODE_SH2A or CS_MODE_SH4A, CS_MODE_SHFPU, and CS_OPT_DETAIL can increment the operand count beyond the 176-byte sh_info allocation and perform a four-byte heap buffer overflow write. The corruption can crash the process and may enable code execution depending on heap layout. This issue is fixed in version 6.0.0-Alpha10.

## Remediation

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