# CVE-2026-78439: Microsoft Graphics Component stack-based buffer overflow

Source: https://junglewise.ai/threats/cve-2026-78439-microsoft-graphics-component-stack-based-buffer-overflow  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-08. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-78439 · Severity: high · CVSS 8.8 · Published 2026-09-08

Microsoft's Graphics Component contains a stack-based buffer overflow vulnerability that allows attackers to execute arbitrary code remotely without authentication. An attacker can exploit this flaw by sending specially crafted network traffic to a system running the vulnerable component, potentially leading to complete system compromise, data theft, or malware installation.

Technologies: [Microsoft Graphics Component](https://junglewise.ai/threats/technologies/graphics-component). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-78439 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-78439 being exploited in the wild.

**How severe is CVE-2026-78439?** High severity, with a CVSS score of 8.8, published 8 September 2026.

**Which products and versions are affected?** Microsoft Graphics Component.

**Is there a fix for CVE-2026-78439?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-78439 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-78439?** Check whether you run Microsoft Graphics Component. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a stack-based buffer overflow in the Microsoft Graphics Component, allowing remote code execution over the network without requiring prior authentication or user interaction. The attack vector is network-based, meaning an attacker can exploit this flaw by sending malicious packets to an exposed service. The vulnerability enables an attacker to overwrite the call stack and redirect execution flow to execute arbitrary code with the privileges of the affected process. Microsoft has released security updates to address this issue; systems should be patched immediately to mitigate the risk.

## Affected products

- Microsoft Graphics Component

## Timeline

- 2026-09-08: disclosed

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78439](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78439)

## Related threats

- [Microsoft Graphics Component out-of-bounds read](https://junglewise.ai/threats/cve-2026-112754-out-of-bounds-read-in-microsoft-graphics-component-allows-an)
- [Microsoft Graphics Component stack buffer overflow](https://junglewise.ai/threats/cve-2026-85881-stack-based-buffer-overflow-in-microsoft-graphics-component)
- [Microsoft Graphics Component out-of-bounds read privilege elevation](https://junglewise.ai/threats/cve-2026-85338-out-of-bounds-read-in-microsoft-graphics-component-allows-an)
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- [Microsoft Graphics Component information disclosure](https://junglewise.ai/threats/cve-2026-105731-use-of-uninitialized-resource-in-microsoft-graphics-component)