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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-55893 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
CVSS-B 7.3 HIGH
Vector:  CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/capstone-engine/capstone/commit/09e76802380b9e94d9720c44458d9d5282219e7e GitHub, Inc.
https://github.com/capstone-engine/capstone/commit/e17ee44a8307ea33375b4727ac4f987650bf7bed GitHub, Inc.
https://github.com/capstone-engine/capstone/pull/2968 GitHub, Inc.
https://github.com/capstone-engine/capstone/pull/2969 GitHub, Inc.
https://github.com/capstone-engine/capstone/releases/tag/6.0.0-Alpha10 GitHub, Inc.
https://github.com/capstone-engine/capstone/security/advisories/GHSA-3hpv-wr3j-rxwh GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-122 Heap-based Buffer Overflow GitHub, Inc.  

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-55893
NVD Published Date:
08/20/2026
NVD Last Modified:
08/21/2026
Source:
GitHub, Inc.