CVE-2026-53136
HIGHIn the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Clamp VBIOS HDMI retimer register count to array size [Why & How] The VBIOS integrated info tables…
Description
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Clamp VBIOS HDMI retimer register count to array size
[Why & How] The VBIOS integrated info tables (v1_11 and v2_1) contain HdmiRegNum and Hdmi6GRegNum fields that are used as loop bounds when copying retimer I2C register settings into fixed-size arrays (dp_ext_hdmi_reg_settings[9] and dp_ext_hdmi_6g_reg_settings[3]). These u8 fields are not validated before use, so a malformed VBIOS can specify values up to 255, causing an out-of-bounds heap write during driver probe.
Clamp each register count to the destination array size using min_t() before the copy loops, in both get_integrated_info_v11() and get_integrated_info_v2_1().
(cherry picked from commit 5a7f0ef90195940c54b0f5bb85b87da55f038c69)
Affected Products
linux kernellinuxDetection & mitigation playbook
Vendor / applianceDetect
Inventory every linux linux kernel deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for exploitation at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.
Fix
Apply the linux linux kernel security patch or hotfix for CVE-2026-53136 on the affected version, following the vendor advisory for your exact build.
Workarounds
Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.
How O3 protects you
O3 detects and blocks CVE-2026-53136 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.
Tailored to CVE-2026-53136. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-53136 being exploited in your environment?
O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2026-53136 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.