CVE-2026-103567 in Windows
Summary
by MITRE • 10/13/2026
Buffer over-read in Windows Broadcast DVR User Service allows an authorized attacker to disclose information locally.
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Analysis
by VulDB Data Team • 10/15/2026
The vulnerability identified as a buffer over-read within the Windows Broadcast DVR User Service represents a significant security risk that primarily affects local system integrity and confidentiality. This specific service, often associated with digital video recording functionalities on Windows operating systems, contains a flaw where it fails to properly validate memory boundaries during data processing operations. When an authorized attacker interacts with this component, they can trigger a condition where the application reads beyond the allocated buffer limits. Unlike more severe vulnerabilities that allow for arbitrary code execution or privilege escalation, this particular defect is classified as an information disclosure vulnerability because its primary consequence is the leakage of sensitive data residing in adjacent memory locations rather than direct control over system processes.
From a technical perspective, the root cause lies in improper input validation and boundary checking mechanisms within the service's handling of broadcast DVR-related inputs. The attacker must possess valid authentication credentials to exploit this flaw, which limits the attack vector to local access scenarios. By carefully crafting specific requests or interactions with the Broadcast DVR User Service, an authorized user can induce a state where memory contents outside the intended buffer are exposed. This exposure may reveal internal system states, cryptographic keys, session tokens, or other sensitive information that was not intended for public consumption. The severity of this issue is compounded by its potential to facilitate further attacks if the disclosed information provides insights into system architecture or security configurations.
The operational impact of this vulnerability centers on the compromise of confidentiality rather than availability or integrity in the traditional sense. While an authorized attacker can already perform many actions within their permission scope, gaining access to additional memory contents could reveal credentials or configuration details that aid in lateral movement or deeper infiltration attempts. This aligns with common weakness enumerations such as CWE-126 Buffer Over-read, which highlights risks associated with reading beyond buffer boundaries. Furthermore, from a tactical standpoint, this behavior corresponds to ATT&CK techniques related to Credential Dumping and System Information Discovery, specifically under local data access patterns where attackers seek to gather intelligence for subsequent exploitation phases.
Mitigation strategies should focus on both immediate remediation and long-term architectural improvements. Microsoft typically addresses such issues through security updates that patch the underlying code defects within the Broadcast DVR User Service. Administrators are advised to apply these patches promptly upon release to close the information disclosure vector. Additionally, since the vulnerability requires local access by an authorized user, enforcing strict least-privilege principles is crucial. Limiting which users can interact with broadcast-related services reduces the attack surface significantly. Regular auditing of service permissions and monitoring for unusual memory access patterns can also help detect potential exploitation attempts before significant data leakage occurs.