Description
Capstone is a disassembly framework. Versions prior to 6.0.0-Alpha8 and 5.0.8 have a NULL pointer dereference in `modRMRequired()` and `decode()` when disassembling 3DNow! opcodes (`0F 0F`) in builds compiled with `-DCAPSTONE_X86_REDUCE`, allowing a remote attacker to crash any application using the reduced X86 Capstone library by supplying a crafted input containing the 4-byte sequence `0F 0F <modrm> <imm8>`. Versions 6.0.0-Alpha8 and 5.0.8 patch the issue.
Affected products
capstone-engine: capstone
References5
- github.com/capstone-engine/capstone/security/advisories/GHSA-28… ExploitVendor Advisory
- github.com/capstone-engine/capstone/security/advisories/GHSA-28… ExploitVendor Advisory
- github.com/capstone-engine/capstone/commit/a0201371719b5aaa91d3… Patch
- github.com/capstone-engine/capstone/commit/fab595205fee206f5c21… Patch
- github.com/capstone-engine/capstone/pull/2924 Issue TrackingPatch
Metrics
- CVSS 3.1
-
5.9
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 41 · as of 14 November 2026
- CWE
- CWE-476
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.