CVE-2026-33824: Microsoft Internet Key Exchange (IKE) Service Extensions Double Free Vulnerability

In short

Microsoft Internet Key Exchange (IKE) Service Extensions has a weakness classified as double free (CWE-415). CISA added it to its Known Exploited Vulnerabilities catalog on 2026-08-18. NVD lists CVSS 3.1 at 9.8 CRITICAL.

What it is

“Microsoft Internet Key Exchange (IKE) Service Extensions contains a double free vulnerability that could enable remote code execution.” — CISA KEV, retrieved 2026-11-01

“Double free in Windows IKE Extension allows an unauthorized attacker to execute code over a network.” — NVD, retrieved 2026-11-01

Who is affected

Microsoft Internet Key Exchange (IKE) Service Extensions. NVD lists the following versions as affected:

• Microsoft Windows 10 1607: before 10.0.14393.9060
• Microsoft Windows 10 1809: before 10.0.17763.8644
• Microsoft Windows 10 21h2: before 10.0.19044.7184
• Microsoft Windows 10 22h2: before 10.0.19045.7184
• Microsoft Windows 11 23h2: before 10.0.22631.6936
• Microsoft Windows 11 24h2: before 10.0.26100.8246
• Microsoft Windows 11 25h2: before 10.0.26200.8246
• Microsoft Windows 11 26h1: before 10.0.28000.1836
• Microsoft Windows Server 2016: before 10.0.14393.9060
• Microsoft Windows Server 2019: before 10.0.17763.8644
• Microsoft Windows Server 2022: before 10.0.20348.5020
• Microsoft Windows Server 2022 23h2: before 10.0.25398.2274
• Microsoft Windows Server 2025: before 10.0.26100.32690

Exploitation status

CISA KEV added: 2026-08-18. Known ransomware campaign use: Not reported by CISA. Due date CISA set for US federal civilian agencies: 2026-08-21.

Scores

NVD CVSS 3.1: 9.8 CRITICAL; vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H; source [email protected].

EPSS by FIRST: 77.05%; percentile 99.55; score date 2026-10-31. EPSS estimates the probability of exploitation in the next 30 days.

CWE: CWE-415.

Timeline

CISA required action

“Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.” — CISA KEV

What to do

• Confirm whether you run Microsoft Internet Key Exchange (IKE) Service Extensions and which version.
• Apply the vendor update or mitigation in the advisory.
• Follow CISA’s required action.
• Review the vendor guidance on signs of compromise.
• Track the fix through completion.

References

• Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33824
• Third Party Advisory: https://unit42.paloaltonetworks.com/autonomous-ai-cyber-attack-campaign/
• NVD detail
• CVE.org record
• CISA KEV catalog

Sources and dates

CISA Known Exploited Vulnerabilities Catalog, version 2026.10.30; retrieved 2026-11-01. CISA KEV data: CC0 1.0. No endorsement by CISA.

NVD retrieved: 2026-11-01. This product uses the NVD API but is not endorsed or certified by the NVD.

EPSS scores by FIRST; score date 2026-10-31.