CVE-2026-53178 in Linux
Summary
by MITRE • 06/25/2026
In the Linux kernel, the following vulnerability has been resolved:
staging: rtl8723bs: rtw_mlme: add bounds checks before ie_length subtraction
Add guards to ensure ie_length is large enough before subtracting fixed IE offsets to prevent unsigned integer underflow.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 06/25/2026
The vulnerability in question affects the staging driver for rtl8723bs wireless network adapters within the Linux kernel ecosystem. This issue resides in the rtw_mlme component responsible for managing wireless network management operations including beacon processing and information element handling. The problem manifests as a potential unsigned integer underflow condition that could lead to unpredictable behavior during wireless communication processing. The vulnerability specifically impacts devices using Realtek RTL8723BS chipsets which are commonly found in various embedded systems and portable computing devices.
The technical flaw occurs within the information element processing logic where the driver attempts to subtract fixed offsets from the ie_length variable without proper validation of its minimum value. When processing beacon frames or probe response packets, the driver reads the length of information elements and subsequently performs arithmetic operations that assume sufficient data exists. However, if an attacker can craft malicious wireless frames with carefully constructed information element lengths, they can cause the unsigned integer subtraction to wrap around to a very large positive value, effectively creating an underflow condition.
This type of vulnerability falls under the category of CWE-191 Integer Underflow (Wrap or Wraparound) which is classified as a fundamental arithmetic error that can lead to memory corruption and potentially arbitrary code execution. The vulnerability demonstrates characteristics consistent with ATT&CK technique T1059.007 Command and Scripting Interpreter: PowerShell, where malicious input could be crafted to exploit the integer underflow condition and potentially gain elevated privileges within the kernel space. The underlying issue represents a classic bounds checking failure that allows attackers to manipulate memory layout through crafted wireless frames.
The operational impact of this vulnerability extends beyond simple denial of service conditions. An attacker positioned within wireless range of affected devices could potentially trigger kernel memory corruption, leading to system crashes or more severe exploitation scenarios. The vulnerability affects all systems running Linux kernels with the rtl8723bs driver enabled, particularly impacting embedded devices, laptops, and IoT appliances that utilize this specific wireless chipset. Mobile devices such as smartphones and tablets using these adapters would be at risk if they process wireless frames without proper validation of information element lengths.
Mitigation strategies should focus on implementing proper bounds checking before any arithmetic operations involving unsigned integers. The fix requires adding conditional checks to ensure ie_length remains above minimum thresholds before performing subtraction operations with fixed offsets. System administrators should ensure all kernel updates are applied promptly, as this vulnerability has been addressed in upstream kernel releases. Additionally, network monitoring tools should be employed to detect anomalous wireless frame patterns that could indicate exploitation attempts. Device manufacturers should implement runtime validation of wireless frame parameters and consider deploying intrusion detection systems specifically designed to monitor for suspicious information element structures. The solution aligns with security best practices outlined in the Linux Kernel Security documentation and represents a standard defensive programming approach to prevent integer overflow and underflow conditions.