Microsoft fixes Always On VPN failures from September Windows 11 updates
KB5127936 stops connections stuck on Connecting or reporting a port already in use; a single-protocol workaround remains.
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Stories tagged #ikev2
Study compares eight ways to carry large PQC KEMs in IKEv2
Across 126,500 handshakes, no design fully offsets key size, and Classic McEliece fails under hard loss.
Microsoft says October updates did not fix Always On VPN bug
After an initial failure, automatic IKEv2 and SSTP fallback can leave connections stuck or report a port already in use.
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Composite IKEv2 key sharing cuts PQC handshake time under packet loss
At 1% packet loss the composite handshake is at least 20% faster than hybrid methods, and 30% faster at 10% loss.
Microsoft: September Windows updates break Always On VPN connections
September 2026 Windows updates break Always On VPN connections when automatic protocol selection is enabled.
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Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software IKEv2 Certificate Authentication Denial of Service Vulnerability
Cisco patched an ASA/FTD IKEv2 certificate authentication flaw letting unauthenticated remote attackers crash the IKEv2 process and reload devices with crafted certificates.
ZDI-26-622: Microsoft Windows IKEv2 AES-GCM Decryption Integer Underflow Remote Code Execution Vulnerability
ZDI disclosed CVE-2026-50696, a CVSS 8.1 integer underflow in Windows IKEv2 AES-GCM decryption enabling unauthenticated remote code execution on specific IPsec configurations.
Zero Day Initiative — CVE-2026-33824: Remote Code Execution in Windows ...
ZDI details CVE-2026-33824, a double-free in Windows IKEv2 fragment reassembly enabling unauthenticated remote code execution as SYSTEM on Windows.
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