CVE-2023-40296 in async-sockets-cpp
Summary
by MITRE • 08/14/2023
async-sockets-cpp through 0.3.1 has a stack-based buffer overflow in ReceiveFrom and Receive in udpsocket.hpp when processing malformed UDP packets.
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Analysis
by VulDB Data Team • 01/27/2026
The vulnerability identified as CVE-2023-40296 affects the async-sockets-cpp library version 0.3.1 and earlier, presenting a critical stack-based buffer overflow condition within the UDP socket implementation. This flaw manifests specifically in the ReceiveFrom and Receive functions located in the udpsocket.hpp file, where the library fails to properly validate input data when processing UDP packets. The issue arises from inadequate bounds checking mechanisms that allow maliciously crafted UDP packets to overwrite adjacent stack memory regions, potentially leading to arbitrary code execution or system instability.
The technical implementation of this vulnerability stems from improper handling of packet data length during network reception operations. When the async-sockets-cpp library processes incoming UDP packets, it does not sufficiently validate the size of incoming data against the allocated buffer space in the ReceiveFrom and Receive functions. This allows attackers to craft UDP packets with oversized payload data that exceeds the predetermined buffer limits, causing a classic stack buffer overflow condition. The vulnerability aligns with CWE-121 Stack-based Buffer Overflow, which specifically addresses buffer overflows occurring in stack memory regions due to insufficient bounds checking.
From an operational perspective, this vulnerability presents significant risk to systems utilizing the affected library, particularly those handling untrusted network traffic. The buffer overflow could enable remote attackers to execute arbitrary code with the privileges of the affected application, potentially leading to complete system compromise. Attackers could exploit this vulnerability by sending specially crafted UDP packets to any application using the async-sockets-cpp library, making it particularly dangerous in networked environments where such libraries are commonly deployed. The impact extends to applications serving as network services, embedded systems, and any software components that rely on UDP socket functionality for communication.
The exploitability of this vulnerability is enhanced by the fact that UDP protocol inherently lacks connection state verification, making it easier for attackers to send malformed packets without prior connection establishment. Network administrators and developers should consider implementing defensive measures such as input validation at multiple layers, including network-level packet filtering and application-level data sanitization. The recommended mitigation strategy involves immediate upgrade to version 0.3.2 or later of the async-sockets-cpp library, which includes proper bounds checking and input validation mechanisms. Additionally, implementing network segmentation and using intrusion detection systems can help detect and prevent exploitation attempts targeting this vulnerability.
Security practitioners should also reference ATT&CK framework techniques related to command and control communications and remote code execution to understand potential attack vectors. The vulnerability demonstrates how seemingly benign network protocols can become attack surfaces when proper input validation is omitted, highlighting the importance of defensive programming practices. Organizations using this library should conduct comprehensive vulnerability assessments and implement continuous monitoring to detect potential exploitation attempts. The remediation process should include not only software updates but also code review practices to ensure similar buffer overflow vulnerabilities are not present in other network handling components within the application stack.