CVE-2025-29828: 
vulnerability analysis and mitigation

CVE-2025-29828 is a Critical remote code execution vulnerability discovered in Windows Cryptographic Services (Schannel) that was disclosed and patched in June 2025. The vulnerability stems from a missing release of memory after effective lifetime in Windows Cryptographic Services, which allows an unauthorized attacker to execute code over a network (NVD, Wiz).

The vulnerability has been assigned a CVSS v3.1 base score of 8.1 (HIGH) with the vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H. The exploitation requires sending a flood of malicious fragmented ClientHello messages to a target server accepting TLS connections, which makes the exploit potentially detectable (Wiz).

If successfully exploited, this vulnerability allows an attacker to execute arbitrary code on affected systems through the Windows Cryptographic Services. The vulnerability affects the confidentiality, integrity, and availability of the target system, as indicated by the CVSS scoring (Wiz).

Microsoft has released security updates to address this vulnerability as part of the June 2025 Patch Tuesday updates. Organizations are advised to apply the security updates immediately to protect against potential exploitation (Wiz).