Medium severity · published Jul 21, 2026
CVE-2026-47143
Capstone has a NULL Pointer Dereference with 3DNow! opcodes
5.9
CVSS
0.5%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 40% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CA
capstone · capstone-engine
< 5.0.8; < 6.0.0-Alpha8 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-47143
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-47143
Patch
https://github.com/capstone-engine/capstone/commit/a0201371719b5aaa91d318ab2898843718f92d1f
Patch
https://github.com/capstone-engine/capstone/commit/fab595205fee206f5c21be6ed8ad2eaf9225f1c7
Issue Tracking
https://github.com/capstone-engine/capstone/pull/2924
Exploit
https://github.com/capstone-engine/capstone/security/advisories/GHSA-289w-cm54-fgrm
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