Source: cve@mitre.org
An issue was discovered in the stack crate before 0.3.1 for Rust. ArrayVec has an out-of-bounds write via element insertion.
Critical vulnerability exists in the stack crate for Rust, allowing for an out-of-bounds write due to an error in the ArrayVec implementation. This flaw could lead to arbitrary code execution, denial of service, or information disclosure in applications utilizing the affected crate. Successful exploitation could compromise system integrity and confidentiality.
Step 1: Target Identification: Identify applications or services that use the vulnerable stack crate (versions before 0.3.1) and specifically employ the ArrayVec data structure.
Step 2: Input Manipulation: Craft a malicious input that triggers the out-of-bounds write. This involves providing data that, when processed by the ArrayVec's insertion functions, causes an overflow.
Step 3: Triggering the Vulnerability: The crafted input is fed to the application. The ArrayVec attempts to insert elements beyond its allocated capacity.
Step 4: Out-of-Bounds Write: Due to the missing or insufficient bounds checks, the insertion operation writes data outside the allocated memory region of the ArrayVec.
Step 5: Impact: The out-of-bounds write overwrites adjacent memory, potentially corrupting other data structures, control flow, or even allowing for arbitrary code execution. This could lead to a crash (DoS), information disclosure, or full system compromise.
The vulnerability stems from an out-of-bounds write within the ArrayVec data structure in the stack crate. Specifically, the flaw allows an attacker to insert elements into the ArrayVec beyond its allocated buffer size. The root cause is a logic error in the insertion logic, where the bounds checks are insufficient or missing, leading to a buffer overflow. This occurs when the code fails to properly validate the index or capacity before writing to the underlying array. The lack of proper bounds checking allows for writing data outside the allocated memory region, potentially overwriting adjacent data structures, control flow data, or even executing malicious code. The vulnerability is triggered by manipulating the insertion operations, such as insert() or similar methods, in a way that exceeds the array's capacity. This can lead to a heap overflow or stack overflow, depending on where the ArrayVec is allocated.
Due to the nature of the vulnerability, it's likely that any threat actor with the technical capability could exploit this. There is no specific APT group or malware family directly linked to this CVE. However, any actor targeting Rust-based applications could potentially leverage this vulnerability. This CVE is not listed on the CISA KEV at this time.
Monitor application logs for unusual behavior related to the stack crate, such as unexpected crashes or errors during array insertion operations.
Implement memory safety checks and instrumentation to detect out-of-bounds writes or memory corruption.
Analyze core dumps or crash reports for evidence of memory corruption related to the ArrayVec data structure.
Network traffic analysis: Look for unusual network activity originating from systems running vulnerable applications, especially after input that could trigger the vulnerability.
File system monitoring: Check for modifications to files or directories that could indicate exploitation, such as the creation of new executable files or changes to system configuration files.
Upgrade the stack crate to version 0.3.1 or later. This version includes the fix for the out-of-bounds write vulnerability.
Review and audit the code that uses the ArrayVec data structure to ensure proper bounds checking and input validation.
Implement robust input validation to prevent malicious input from triggering the vulnerability.
Use memory safety tools and techniques, such as fuzzing and static analysis, to identify and prevent similar vulnerabilities.
Apply the principle of least privilege: Limit the permissions of applications that use the stack crate to minimize the impact of a successful exploit.
Regularly update all dependencies to the latest versions to address known vulnerabilities.