External risk intelligence

Capstone Stack Buffer Underflow Overflow CVE-2025-68114

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2025-68114

Capstone is a disassembly framework used as a software library linked into other applications to perform code analysis. It is not a network-facing service, appliance, or gateway. Vulnerabilities in a library typically require the processing of untrusted input by an application that uses the library, making direct public-internet exposure of the library itself extremely unlikely.

Buffer Overflow

Capstone Engine Capstone

before 6.0.06.0.0

Halo Surface Signal: 1 out of 5 — much less likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A vulnerability has been identified in the Capstone disassembly framework, a widely used software library. This issue could allow for memory corruption, potentially impacting the integrity and availability of systems that rely on this framework for code analysis. The primary concern is confirming the relevance and exposure of this library within our environment.

Malicious input can corrupt memory in the framework.
This library is critical for code analysis tools.
Confirm our use and exposure to this component.

Attack Path

How an attacker could exploit the issue

An attacker could submit specially crafted input to the Capstone disassembly framework, which is often integrated as a library into other applications. This malicious input, processed by the `SStream_concat` function, can manipulate internal indexing, leading to a buffer underflow or overflow on the stack during subsequent operations. If successfully triggered, this vulnerability could allow an attacker to achieve significant impact.

No authentication or user interaction required.
Triggered by processing malicious input.
Leads to stack buffer corruption.

Live Threat

Current exploitation, exposure, and threat context

This vulnerability could affect system data processed by the Capstone disassembly framework when handling specially crafted input, potentially leading to unexpected behavior or data corruption.

Disassembly framework data integrity.
Malicious input processing.
System instability or data corruption.

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability affects the Capstone disassembly framework, likely used as a library within other applications. Ownership will depend on how Capstone is integrated; application owners must coordinate with platform or infrastructure teams. The first practical step is to identify all systems where Capstone is deployed, determine business criticality and external reachability, and then confirm the accountable owner for remediation planning.

Identify systems deploying Capstone.
Confirm business criticality and exposure.
Plan remediation with accountable owner.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

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Frequently asked questions

What is the Capstone disassembly framework?

Capstone is a lightweight multi-architecture disassembly framework used as a software library. Developers integrate it into their own applications—such as debuggers, binary analysis tools, and security scanners—to translate machine code instructions into human-readable formats.

How does CVE-2025-68114 cause memory corruption?

This vulnerability involves a buffer underflow or overflow, classified as CWE-120 and CWE-124. It happens because the SStream_concat function does not properly validate return values from a memory-copying operation. This oversight allows an attacker to manipulate internal index pointers, leading to memory being written outside of intended bounds.

Do I need malicious input to trigger this bug?

Yes. The vulnerability is triggered when the framework processes specially crafted, malicious input. If the framework is processing benign or well-formatted code, the indexing issue remains dormant. The flaw relies on providing inputs specifically designed to force the software into an invalid memory operation.

Is my system at risk if I use Capstone?

Halo Surface Signal indicates that direct internet exposure of Capstone is very unlikely because it is a library, not a standalone service. The risk depends on whether your internal applications pass untrusted, attacker-controlled data into the framework's disassembly functions.

When should I update my software to fix this?

You should begin by auditing your software inventory to locate where Capstone is integrated. Since this is a library, you must identify which of your applications use affected versions and coordinate with those specific development teams to update to a patched version.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.