CVE-2024-49990

What it actually does

Null pointer dereference in the Linux kernel drm/xe/hdcp code path when xe_gsc structure is uninitialized during HDCP capability checks.

Why it matters to the business

Kernel crashes or system instability on affected Linux distributions using Intel Xe graphics hardware, potentially causing downtime or requiring reboots; low urgency due to stable low EPSS and no KEV listing.

How an attack unfolds

An attacker with local access triggers the HDCP capability check code path in a scenario where the GSC structure has not been initialized, leading to a null pointer dereference and kernel panic; no named threat actors or ransomware campaigns are associated.

How to fix it

Upgrade to fixed kernel versions such as kernel-rt 4.18.0-305.17.1.rt7.89.el8_4 on Rocky Linux 8 or apply commit c940627857eedca8407b84b40ceb4252b100d291 in the stable Linux kernel tree.

How to confirm the fix worked

Verify the running kernel version matches or exceeds the listed fixed versions; inspect kernel source for the added GSC structure validity check in drm/xe/hdcp.

Typical attack path

1. Obtain local access to a vulnerable Linux system with Intel Xe graphics
2. Trigger HDCP-related functionality or capability checks
3. Cause xe_gsc to remain uninitialized
4. Trigger null pointer dereference resulting in kernel oops or panic

How to detect it

Review kernel logs for null pointer dereference oops messages referencing drm/xe or hdcp and gsc structures; check for unexpected system reboots or panics after HDCP-related operations.

• xe_gsc
• drm/xe/hdcp
• null pointer
• GSC structure validity

What your security team should do

• Apply the kernel update to fixed versions immediately on affected systems
• Monitor for kernel stability issues on systems with Intel Xe graphics
• Prioritize patching in environments with HDCP-enabled displays