Copyright © 2012 Red Hat, Inc. All rights reserved. Moderate 2026-08-20T21:32:46 capstone: Capstone: Heap buffer overflow with potential code execution 7.0 CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H CWE-805

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.

A flaw was found in Capstone, a disassembly framework. The SH floating-point decoders in `arch/SH/SHDisassembler.c` do not correctly validate the size of the `operands[]` array when processing certain instructions. This vulnerability allows a local attacker to provide specially crafted SH2A FPU bytecode, leading to a heap buffer overflow. Successful exploitation can cause the application to crash, resulting in a Denial of Service (DoS), and may potentially enable arbitrary code execution.

Red Hat Hardened Images 2026-08-25T00:00:00Z RHSA-2026:59419 capstone-main-5.0.8-0.3.hum1 Red Hat Enterprise Linux 10 Affected capstone Red Hat Enterprise Linux 9 Affected capstone Red Hat OpenShift Container Platform 4 Affected openshift/ose-rhel-coreos-9 https://www.cve.org/CVERecord?id=CVE-2026-55893 https://nvd.nist.gov/vuln/detail/CVE-2026-55893 https://github.com/capstone-engine/capstone/commit/09e76802380b9e94d9720c44458d9d5282219e7e https://github.com/capstone-engine/capstone/commit/e17ee44a8307ea33375b4727ac4f987650bf7bed https://github.com/capstone-engine/capstone/pull/2968 https://github.com/capstone-engine/capstone/pull/2969 https://github.com/capstone-engine/capstone/releases/tag/6.0.0-Alpha10 https://github.com/capstone-engine/capstone/security/advisories/GHSA-3hpv-wr3j-rxwh