# CVE-2026-83521: Microsoft Windows IKE Extension out-of-bounds read

Source: https://junglewise.ai/threats/cve-2026-83521-out-of-bounds-read-in-windows-ike-extension-allows-an-authorized  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-13. Updated: 2026-10-16  
License: CC BY 4.0 with a link back

CVE-2026-83521 · Severity: medium · CVSS 6.5 · Published 2026-10-13

Windows IKE Extension, a component that handles encrypted network communications for virtual private networks (VPNs), contains an out-of-bounds read vulnerability. An authorized attacker on the network could exploit this to read sensitive information from the system's memory, potentially exposing credentials or other confidential data.

Technologies: [Microsoft Windows IKE Extension](https://junglewise.ai/threats/technologies/windows-ike-extension). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-83521 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-83521 being exploited in the wild.

**How severe is CVE-2026-83521?** Medium severity, with a CVSS score of 6.5, published 13 October 2026.

**Which products and versions are affected?** Microsoft Windows IKE Extension.

**Is there a fix for CVE-2026-83521?** 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-2026-83521 attacked?** It is attacked over the network, in an operating system.

**Am I affected by CVE-2026-83521?** Check whether you run Microsoft Windows IKE Extension. 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

Out-of-bounds read in the Windows IKE (Internet Key Exchange) Extension allows an authorized, network-adjacent attacker to disclose sensitive information. The vulnerability requires the attacker to be authenticated and able to send crafted network packets to the vulnerable component. Successful exploitation could leak confidential data from kernel memory.

## Affected products

- Microsoft Windows IKE Extension

## Timeline

- 2026-10-13: disclosed

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83521](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83521)

## Related threats

- [Microsoft Windows IKE Extension access control bypass allows spoofing](https://junglewise.ai/threats/cve-2026-122169-insufficient-granularity-of-access-control-in-windows-ike)
- [Microsoft Windows IKE Extension null pointer dereference](https://junglewise.ai/threats/cve-2026-69881-microsoft-windows-ike-extension-null-pointer-dereference)
- [Microsoft Windows IKE Extension null pointer dereference](https://junglewise.ai/threats/cve-2026-69587-microsoft-windows-ike-extension-null-pointer-dereference)
- [Microsoft Windows IKE Extension heap buffer overflow](https://junglewise.ai/threats/cve-2026-69429-microsoft-windows-ike-extension-heap-buffer-overflow)