CVE-2026-23222 Overview
CVE-2026-23222 is a memory allocation vulnerability in the Linux kernel's OMAP crypto subsystem. The flaw exists in the omap_crypto_copy_sg_lists() function, which was incorrectly allocating an array of scatterlist pointers instead of scatterlist objects. This results in a 4x undersized memory allocation, potentially leading to heap buffer overflows and memory corruption when cryptographic operations are performed on affected systems.
Critical Impact
Memory corruption vulnerability in Linux kernel crypto subsystem affecting OMAP-based systems, including embedded devices and IoT platforms using Texas Instruments processors.
Affected Products
- Linux kernel with OMAP crypto driver enabled
- Texas Instruments OMAP-based embedded systems
- IoT devices and embedded Linux platforms using OMAP processors
Discovery Timeline
- 2026-02-18 - CVE CVE-2026-23222 published to NVD
- 2026-02-19 - Last updated in NVD database
Technical Details for CVE-2026-23222
Vulnerability Analysis
The vulnerability stems from a fundamental programming error in the memory allocation logic within the OMAP crypto driver. When the OMAP_CRYPTO_FORCE_COPY flag is set, the omap_crypto_copy_sg_lists() function allocates memory for scatterlist entries. However, the allocation was using the size of a pointer to a scatterlist structure rather than the size of the scatterlist structure itself.
On 32-bit ARM systems (typical for OMAP processors), a pointer is 4 bytes while the scatterlist structure is significantly larger (typically 16+ bytes). This means the allocated buffer is approximately 4 times smaller than required, creating a classic heap buffer overflow scenario when the function subsequently writes full scatterlist objects into the undersized buffer.
Root Cause
The root cause is an incorrect use of sizeof() in the memory allocation call. The original code was allocating memory based on the size of a pointer (sizeof(struct scatterlist *)) instead of the size of the actual structure (sizeof(struct scatterlist) or sizeof(*new_sg)). This is a common C programming mistake that can have severe security implications in kernel code.
The fix corrects this by using sizeof(*new_sg) to properly calculate the size of scatterlist objects, ensuring adequate memory is allocated for all scatterlist entries.
Attack Vector
Exploitation of this vulnerability would require local access to a system with the OMAP crypto driver loaded. An attacker could potentially trigger the vulnerable code path by performing cryptographic operations that require the OMAP_CRYPTO_FORCE_COPY scatterlist handling. The heap corruption could lead to kernel memory corruption, denial of service through kernel panic, or potentially arbitrary code execution in kernel context.
The vulnerability is particularly concerning for embedded systems and IoT devices using OMAP processors, as these devices often have limited security monitoring capabilities and may run for extended periods without updates.
Detection Methods for CVE-2026-23222
Indicators of Compromise
- Kernel panic or oops messages referencing omap_crypto_copy_sg_lists or related crypto functions
- Unexpected system crashes during cryptographic operations on OMAP-based systems
- Kernel log entries indicating heap corruption or memory allocation failures in crypto subsystem
- Abnormal behavior in applications utilizing hardware crypto acceleration
Detection Strategies
- Monitor kernel logs (dmesg) for OMAP crypto driver errors or memory corruption warnings
- Implement kernel address sanitizer (KASAN) to detect heap buffer overflows during development and testing
- Deploy runtime memory corruption detection tools on affected systems where feasible
- Review system crash dumps for evidence of exploitation attempts targeting the crypto subsystem
Monitoring Recommendations
- Enable kernel crash dump collection to capture evidence of exploitation attempts
- Configure alerting for kernel oops events on systems running affected kernel versions
- Monitor for unusual patterns of cryptographic operations that could indicate exploitation attempts
- Implement integrity monitoring for kernel modules on OMAP-based embedded systems
How to Mitigate CVE-2026-23222
Immediate Actions Required
- Update the Linux kernel to a patched version containing the fix
- Review system configurations to determine if OMAP crypto driver is enabled and in use
- Consider disabling the OMAP crypto driver if not required for system operation
- Prioritize patching for internet-facing or security-critical OMAP-based systems
Patch Information
The Linux kernel development team has released patches addressing this vulnerability across multiple stable kernel branches. The fix corrects the memory allocation by using sizeof(*new_sg) to properly allocate scatterlist objects instead of scatterlist pointers.
Patches are available through the kernel git repositories:
Organizations should update to the latest stable kernel version for their distribution or apply the security patches provided by their Linux distribution vendor.
Workarounds
- Disable the OMAP crypto hardware driver by blacklisting the module: add blacklist omap_crypto to /etc/modprobe.d/blacklist.conf
- Use software-based cryptographic implementations instead of OMAP hardware acceleration until patching is complete
- Restrict local system access to trusted users only on affected systems
- Implement additional access controls and monitoring on systems that cannot be immediately patched
# Disable OMAP crypto driver temporarily
echo "blacklist omap_crypto" >> /etc/modprobe.d/blacklist-omap-crypto.conf
# Unload the module if currently loaded
modprobe -r omap_crypto
# Verify module is not loaded
lsmod | grep omap_crypto
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
