CVE-2026-53379 Overview
CVE-2026-53379 is a memory leak vulnerability in the Linux kernel's ov8856 camera sensor driver located at drivers/media/i2c/ov8856.c. The flaw resides in the ov8856_init_controls() function, which failed to release the V4L2 control handler when control registration failed. Repeated initialization failures can exhaust kernel memory over time. The issue has been resolved upstream by adding an error exit label that frees the control handler before returning.
Critical Impact
Failed control initialization in the ov8856 driver leaks the V4L2 control handler, resulting in progressive kernel memory exhaustion on affected systems that repeatedly probe or reinitialize the sensor.
Affected Products
- Linux kernel builds including the media: i2c: ov8856 driver prior to the fix
- Devices using the OmniVision OV8856 image sensor via I2C
- Distributions shipping vulnerable stable kernel branches referenced in the upstream commits
Discovery Timeline
- 2026-07-19 - CVE-2026-53379 published to NVD
- 2026-07-19 - Last updated in NVD database
Technical Details for CVE-2026-53379
Vulnerability Analysis
The ov8856 driver initializes a V4L2 control handler using v4l2_ctrl_handler_init() and then registers multiple controls with v4l2_ctrl_new_std() and related helpers. If any of these control-registration calls set an error on the handler, the original code path returned an error without invoking v4l2_ctrl_handler_free(). Every failed probe therefore leaked the handler allocation and its associated control objects.
The fix introduces a dedicated error exit label. Failing paths now jump to this label, which calls the handler free routine before propagating the error to the caller. This aligns the driver with the standard V4L2 error-handling pattern used elsewhere in the media subsystem.
Root Cause
The defect is a resource cleanup omission classified as a memory leak. The function acquired kernel memory for the control handler but lacked a corresponding release path on the error branch, violating the allocate-then-free contract required for V4L2 handlers.
Attack Vector
The vulnerability is not remotely reachable and requires the presence of the OV8856 sensor plus conditions that cause control registration to fail, such as I2C errors or resource pressure. Impact is limited to kernel memory exhaustion; there is no indication of code execution or privilege escalation. No public exploit is available, and the EPSS score is 0.161%.
No verified proof-of-concept code is published for this issue. Refer to the upstream commits for the exact source-level changes.
Detection Methods for CVE-2026-53379
Indicators of Compromise
- Repeated ov8856 probe failure messages in dmesg or the kernel log ring buffer
- Growth in Slab and SUnreclaim values in /proc/meminfo correlating with camera subsystem activity
- V4L2 handler allocations retained after driver unbind events, visible through kmemleak reports
Detection Strategies
- Enable CONFIG_DEBUG_KMEMLEAK on test kernels and inspect /sys/kernel/debug/kmemleak for v4l2_ctrl_handler_init allocations that are never freed
- Correlate I2C bus errors on the OV8856 address with subsequent memory growth using kernel tracing tools such as ftrace or bpftrace
- Track kernel package versions against the fixed commits referenced in the NVD entry to identify unpatched hosts
Monitoring Recommendations
- Alert on abnormal kernel slab growth on devices equipped with OV8856 sensors, including laptops and embedded platforms
- Collect dmesg telemetry centrally and flag recurring ov8856_init_controls error returns
- Include kernel version and patch-level attributes in asset inventory to prioritize remediation
How to Mitigate CVE-2026-53379
Immediate Actions Required
- Update to a Linux kernel that includes one of the fix commits: 791598484fd5, ba9e9274c4ec, c13721040a56, d1b3811c6b0f, f727e3251cee, f75e160745663, or fd10fb4c33bd
- Rebuild custom kernels from a stable branch that already carries the backport
- Reboot affected systems after patching to clear leaked handler allocations
Patch Information
The fix adds an error exit label inside ov8856_init_controls() that calls v4l2_ctrl_handler_free() before returning the error code. The patch has been merged to mainline and backported to multiple stable Linux kernel branches. Consult the Linux Kernel stable tree for the specific branch that matches your deployment.
Workarounds
- Unbind the ov8856 driver on systems that do not require the sensor by blacklisting the module in /etc/modprobe.d/
- Restrict access to userspace tools that trigger repeated media device probes on affected hardware
- Monitor and restart long-running services that repeatedly reopen the camera device until the kernel patch is applied
# Blacklist the ov8856 driver until the kernel is patched
echo "blacklist ov8856" | sudo tee /etc/modprobe.d/blacklist-ov8856.conf
sudo update-initramfs -u
sudo reboot
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
