Source: cna@vuldb.com
A weakness has been identified in WebAssembly wabt up to 1.0.39. This vulnerability affects the function wabt::AST::InsertNode of the file /src/repro/wabt/bin/wasm-decompile of the component wasm-decompile. This manipulation causes memory corruption. It is possible to launch the attack on the local host. The exploit has been made available to the public and could be used for attacks. Unfortunately, the project has no active maintainer at the moment. In a reply to the issue report somebody recommended to the researcher to provide a PR himself.
CVE-2025-15411 exposes a critical memory corruption vulnerability within the wabt library, specifically affecting the wabt::AST::InsertNode function in wasm-decompile. This flaw allows attackers to trigger memory corruption, potentially leading to arbitrary code execution and complete system compromise. The lack of active maintainers for the project exacerbates the risk, leaving the vulnerability unpatched and readily exploitable.
Step 1: Crafting the Malicious WebAssembly Module: The attacker creates a specially crafted WebAssembly (.wasm) file. This file is designed to trigger the vulnerability within the wabt::AST::InsertNode function when decompiled.
Step 2: Payload Delivery: The attacker provides the malicious .wasm file to the target system. This could be achieved through various means, such as uploading it to a web server, sending it as an email attachment, or exploiting a file upload vulnerability in a web application.
Step 3: Decompilation Trigger: The target system, which utilizes the vulnerable version of wabt, attempts to decompile the malicious .wasm file using the wasm-decompile tool.
Step 4: Vulnerability Execution: The wasm-decompile tool calls the wabt::AST::InsertNode function with the crafted input. This triggers the memory corruption vulnerability.
Step 5: Memory Corruption: The InsertNode function, due to the identified flaw, corrupts memory. This could involve overwriting critical data structures, function pointers, or other sensitive data.
Step 6: Code Execution (Potential): Depending on the nature of the memory corruption, the attacker may be able to redirect program execution to an address of their choosing, potentially leading to arbitrary code execution and system compromise. This could involve overwriting a function pointer with the address of a malicious payload or manipulating control flow to execute attacker-controlled code.
The vulnerability lies within the wabt::AST::InsertNode function of the wasm-decompile component of the wabt library (versions up to 1.0.39). The root cause is likely a memory corruption issue, potentially a buffer overflow or an out-of-bounds write, triggered during the insertion of nodes within the Abstract Syntax Tree (AST) representation of a WebAssembly module. Specifically, the function InsertNode likely mishandles the allocation or deallocation of memory when inserting or modifying AST nodes. This can lead to overwriting adjacent memory regions, corrupting data structures, and ultimately allowing an attacker to control program execution. The lack of proper bounds checking or incorrect pointer arithmetic within the function is the most probable cause. The exploit leverages a crafted WebAssembly module that, when processed by wasm-decompile, triggers the vulnerable code path in InsertNode.
While no specific APT groups are explicitly linked to this CVE, the public availability of the exploit and the severity of the vulnerability make it attractive to various threat actors. The lack of a patch and the ease of exploitation increase the likelihood of widespread exploitation. CISA KEV status: Not Applicable (as of the provided date, but this could change rapidly).
Monitor file system activity for the execution of wasm-decompile or related wabt tools, especially when processing untrusted .wasm files.
Analyze network traffic for unusual patterns related to WebAssembly module uploads or downloads.
Implement intrusion detection system (IDS) rules to identify attempts to exploit the vulnerability based on known exploit characteristics or signatures.
Monitor system logs for crashes or unexpected behavior related to the wasm-decompile process.
Examine memory dumps or core files generated after crashes for signs of memory corruption, such as overwritten data structures or unexpected code execution paths.
Use static analysis tools to scan WebAssembly modules for potentially malicious code or patterns that could trigger the vulnerability.
Upgrade to a patched version of wabt. Since there is no active maintainer, this is not possible. Consider forking the project and applying a patch.
Implement input validation. Carefully validate all WebAssembly modules before processing them with wasm-decompile or any other vulnerable tool. Reject modules that do not conform to expected standards or contain suspicious features.
Isolate vulnerable components. If possible, run wasm-decompile in a sandboxed environment to limit the impact of a successful exploit.
Disable or restrict access to wasm-decompile. If the functionality is not essential, disable or restrict access to the vulnerable tool.
Monitor for suspicious activity. Implement robust monitoring and logging to detect any attempts to exploit the vulnerability.
Implement a Web Application Firewall (WAF). If the vulnerability is exposed through a web application, a WAF can help to filter malicious requests.