CVE-2025-48823 is a medium severity vulnerability affecting Microsoft Windows 10 Version 1809 (build 10.0.17763.0). The vulnerability arises from cryptographic issues within the Windows Cryptographic Services component, which is responsible for providing cryptographic functions such as encryption, decryption, and secure communications. Specifically, this flaw allows an unauthorized attacker to remotely disclose sensitive information over a network without requiring any authentication or user interaction. The CVSS 3.1 vector (AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N) indicates that the attack can be performed remotely over the network but requires high attack complexity, no privileges, and no user interaction. The impact is primarily on confidentiality, with a high potential for information disclosure, while integrity and availability remain unaffected. No known exploits are currently observed in the wild, and no patches have been linked yet. The underlying weakness is related to CWE-326, which involves the use of weak cryptographic primitives or improper cryptographic implementations, potentially exposing sensitive data to interception or leakage during cryptographic operations. This vulnerability could be exploited by attackers to intercept or extract confidential information transmitted or processed by the affected Windows Cryptographic Services, potentially compromising sensitive organizational data or credentials.

For European organizations, this vulnerability poses a significant risk to the confidentiality of sensitive information, especially for entities relying on Windows 10 Version 1809 in their infrastructure. Since the flaw allows remote information disclosure without authentication, attackers could leverage this to gain insights into internal communications, cryptographic keys, or other sensitive data, which could facilitate further attacks such as lateral movement, espionage, or data exfiltration. Sectors such as finance, healthcare, government, and critical infrastructure in Europe are particularly at risk due to the sensitive nature of their data and regulatory requirements like GDPR that mandate strict data protection. The lack of impact on integrity and availability reduces the risk of service disruption but does not diminish the potential damage from confidentiality breaches. Given that Windows 10 Version 1809 is an older release, organizations that have not upgraded or patched legacy systems remain vulnerable, increasing their exposure to targeted attacks or opportunistic scanning by threat actors.

European organizations should prioritize upgrading affected systems from Windows 10 Version 1809 to a more recent, supported version of Windows 10 or Windows 11 where this vulnerability is not present. In the absence of an official patch, organizations should implement network-level mitigations such as restricting access to Windows Cryptographic Services endpoints via firewalls or network segmentation, limiting exposure to untrusted networks. Monitoring network traffic for anomalous patterns related to cryptographic service communications can help detect potential exploitation attempts. Additionally, organizations should enforce strict cryptographic policies, disable legacy or weak cryptographic protocols where possible, and ensure that all cryptographic libraries and services are configured according to best security practices. Regular vulnerability scanning and asset inventory to identify systems running the affected version are critical to ensure comprehensive remediation. Finally, organizations should stay alert for any forthcoming patches or advisories from Microsoft and apply them promptly once available.