Answer in brief
CVE-2026-55893 records a High severity (CVSS 7.3) vulnerability in Capstone SH disassembler `set_reg_n` heap buffer overflow via crafted SH2A FPU bytecode. The current sources do not mark it as known exploited. The current feed maps capstone-engine/capstone (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps capstone-engine/capstone (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| capstone-engine/capstonegeneric | <6.0.0-Alpha10 | 6.0.0-Alpha10 |
Published upstream
Aug 20, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 18, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 20, 2026
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.
Quoted source text, attributed separately from HOL analysis.