CVE-2026-55894 PUBLISHED

Capstone SH disassembler `sh_disassemble` out-of-bounds read via crafted SH2A bytecode

Assigner: GitHub_M
Reserved: 17.06.2026 Published: 20.08.2026 Updated: 21.08.2026

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.

Metrics

CVSS Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS Score: 6.8

Product Status

Vendor capstone-engine
Product capstone
Versions
  • Version < 6.0.0-Alpha10 is affected

References

Problem Types

  • CWE-125: Out-of-bounds Read CWE