CVE-2026-68247 Overview
CVE-2026-68247 affects the Linux kernel's Intel i915 Direct Rendering Manager (DRM) graphics driver. The vulnerability exists in the Low-power Flat Panel (LFP) Data Block parsing code within the video BIOS (VBIOS) handler. While the driver validates the panel_type field against its expected range, it fails to apply the same range check to the secondary panel_type2 field. Intel Product Security confirmed the issue after AI-assisted static analysis identified the missing validation. Upstream maintainers resolved the flaw by introducing range-check helpers and applying them consistently across panel type selection logic.
Critical Impact
An out-of-bounds read in kernel-space DRM code can lead to memory corruption, information disclosure, or a denial-of-service condition on affected Intel graphics systems.
Affected Products
- Linux kernel builds including the Intel i915 DRM driver prior to the fix commit c9ebe5d2f257
- Systems using Intel integrated graphics that parse the LFP Data Block from VBT (Video BIOS Table)
- Stable Linux kernel branches receiving the cherry-picked backports referenced in the advisory
Discovery Timeline
- 2026-08-10 - CVE-2026-68247 published to the National Vulnerability Database
- 2026-08-10 - Last updated in NVD database
Technical Details for CVE-2026-68247
Vulnerability Analysis
The vulnerability resides in drivers/gpu/drm/i915/display/intel_bios.c, which parses the Low-power Flat Panel (LFP) Data Block from the Intel Video BIOS Table. The driver reads two panel index fields, panel_type and panel_type2, and uses them to index into panel configuration arrays. The original code range-checked panel_type but omitted the equivalent check for panel_type2. An untrusted or malformed VBT can therefore supply a panel_type2 value that exceeds the valid array bounds. Subsequent lookups produce an out-of-bounds read within kernel memory during driver initialization or mode setting. The upstream fix adds is_panel_type() and is_panel_type_pnp() helpers to centralize validation and applies them consistently to both fields.
Root Cause
The root cause is missing input validation on a firmware-supplied index value used for array indexing in kernel code. This is an Out-of-Bounds Read pattern caused by incomplete boundary enforcement over structured firmware data.
Attack Vector
Exploitation requires that the kernel parse an attacker-influenced VBT containing a crafted panel_type2 value. Realistic attack surfaces include physical or firmware-level tampering with platform VBIOS, malicious firmware updates, or virtualized guests that receive attacker-controlled VBT data through paravirtualized display paths. The vulnerability does not appear to be remotely exploitable over the network. No public proof-of-concept or in-the-wild exploitation has been reported.
No verified exploit code is available. Refer to the upstream kernel commits for the exact code paths and remediation logic: Kernel commit c9ebe5d2 and the additional stable backports listed in the advisory.
Detection Methods for CVE-2026-68247
Indicators of Compromise
- Kernel log entries from the i915 driver referencing invalid or out-of-range panel type values during boot or display initialization
- Unexpected DRM subsystem warnings, oops messages, or crashes in intel_bios.c code paths
- Anomalous VBT contents observed via intel_vbt_decode or vendor diagnostic tooling
Detection Strategies
- Inventory Linux hosts and confirm running kernel versions against the fixed builds referenced in the stable tree commits
- Monitor dmesg and journalctl -k output for i915 initialization warnings tied to LFP panel handling
- Correlate DRM kernel warnings with firmware or VBT modification events on developer laptops and workstations
Monitoring Recommendations
- Centralize kernel logs from Linux endpoints and alert on i915 or DRM subsystem oops and WARN traces
- Track firmware and BIOS update events to detect unauthorized VBT modification attempts
- Include kernel version telemetry in vulnerability management dashboards to surface unpatched hosts
How to Mitigate CVE-2026-68247
Immediate Actions Required
- Apply the Linux stable kernel updates containing the four referenced commits to all affected systems
- Prioritize patching on developer workstations, laptops, and virtualization hosts that use Intel integrated graphics
- Restrict physical and administrative access to firmware update interfaces to prevent VBT tampering
Patch Information
The fix is available in the mainline Linux kernel via commit c9ebe5d2f25729d6cfbbb1235d640bf67f9275df and has been backported to stable branches. Reference the four upstream commits: 2084503f, 8887b94d, 8b2da444, and e7b56946. Consume distribution-provided kernel packages once vendors publish updated builds.
Workarounds
- Disable the i915 driver on systems that do not require Intel graphics acceleration until patches are deployed
- Enforce Secure Boot and signed firmware policies to reduce the risk of malicious VBT injection
- Limit exposure of VBT parsing to trusted firmware sources in virtualized environments
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
