CVE-2024-49990 in Linux
Summary
by MITRE • 10/21/2024
In the Linux kernel, the following vulnerability has been resolved:
drm/xe/hdcp: Check GSC structure validity
Sometimes xe_gsc is not initialized when checked at HDCP capability check. Add gsc structure check to avoid null pointer error.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 03/21/2026
The vulnerability identified as CVE-2024-49990 resides within the Linux kernel's display subsystem, specifically affecting the Intel Xe graphics driver's HDCP (High-bandwidth Digital Content Protection) implementation. This issue manifests in the drm/xe/hdcp component where the kernel fails to properly validate the GSC (Graphics Security Controller) structure before attempting to access its properties during HDCP capability checks. The problem occurs during the initialization sequence of the graphics security framework, where the xe_gsc structure may remain uninitialized when the HDCP verification process attempts to reference it, leading to a critical null pointer dereference condition.
The technical flaw stems from inadequate input validation within the graphics security subsystem's HDCP capability detection mechanism. When the kernel attempts to verify HDCP support capabilities, it directly accesses the xe_gsc structure without first confirming whether this structure has been properly initialized. This initialization order dependency creates a race condition scenario where the graphics security controller's data structures are accessed before they are fully constructed, resulting in a null pointer access that can cause system instability or potential privilege escalation. The vulnerability represents a classic case of improper null pointer validation and demonstrates poor defensive programming practices in kernel space code where the assumption of proper initialization order is violated.
The operational impact of this vulnerability extends beyond simple system crashes, potentially allowing malicious actors to exploit the null pointer dereference for privilege escalation attacks within the graphics subsystem. An attacker could leverage this weakness to gain elevated privileges on systems running affected Linux kernels, particularly those utilizing Intel Xe graphics hardware with HDCP support. The vulnerability affects systems where HDCP capability checking is performed during graphics initialization or when content protection features are enabled, making it relevant to multimedia applications, digital rights management systems, and enterprise environments that rely on secure content delivery. The issue is particularly concerning in server environments where graphics processing capabilities are utilized for rendering or virtualization purposes.
Mitigation strategies for CVE-2024-49990 should prioritize applying the latest kernel updates from Linux kernel maintainers, which include the patched implementation that properly validates the GSC structure before access. System administrators should implement immediate patch management protocols to ensure all affected systems receive the security fixes. Additionally, monitoring for abnormal system behavior or kernel panic events during graphics initialization can help detect exploitation attempts. The fix aligns with common security best practices such as input validation and defensive programming principles, addressing the underlying CWE-476 null pointer dereference vulnerability. Organizations should also consider implementing runtime security controls and access restrictions for graphics subsystem components to limit potential exploitation vectors. This vulnerability serves as a reminder of the critical importance of proper initialization sequence handling and input validation in kernel space code, particularly within security-sensitive subsystems where improper handling can lead to privilege escalation and system compromise. The remediation process should include comprehensive testing of graphics functionality post-patch to ensure that HDCP capabilities remain fully operational while eliminating the null pointer dereference condition.