A researcher has uncovered four novel methods to manipulate Windows Explorer, enabling the spoofing of targets, concealment of arguments, and execution of unintended programs, all by embedding conflicting metadata within LNK files.
The potential for misusing Windows shortcut (.LNK) files continues to expand, with a cybersecurity researcher detailing four fresh techniques to deceive Windows users into performing harmful operations via seemingly benign shortcuts.
Wietze Beukema illustrated methods to falsify the displayed LNK destination, obscure command-line arguments, and launch a different application than what is presented to the user. This could furnish attackers with novel avenues for phishing scams, USB-based intrusions, or initial network infiltration.
This revelation further fuels persistent worries regarding a persistent vulnerability in LNK file processing, which, despite repeated exploitation by malicious entities, has remained stubbornly hard to eradicate.
While Microsoft offered no immediate comment on this particular disclosure, the company has previously recognized potential hazards in this domain, issuing security advice such as a November 2025 advisory.
To date, Microsoft has consistently refrained from categorizing Windows’ interaction with LNK files as a standard “vulnerability.” However, the extensive array of exploits showcased by Beukema increasingly challenges Microsoft’s assertion that this is merely a user interface problem.
Deception Tactics
Beyond merely pointing to applications or documents, Windows shortcuts can contain diverse information. LNK files are capable of dictating command-line arguments, operational directories, icons, and various other execution settings, thereby functioning as comprehensive program launchers.
Beukema uncovered several hitherto unknown methods for creating discrepancies between the perceived target of a Windows shortcut and its actual execution point. Given that the LNK format permits the storage of the target path across various structures—such as “TargetIDList,” “EnvironmentVariableDataBlock,” and “LinkInfo” fields—Windows is compelled to decide which value takes precedence. This decision-making logic is susceptible to manipulation.
Beukema explains that typically, if both an EnvironmentVariableDataBlock and a TargetIDList exist, Windows Explorer favors the EnvironmentVariableDataBlock, using and showing that particular path. Nevertheless, should the Environment Variable path be syntactically flawed, Explorer will still present it within the Properties dialogue yet will covertly revert to the concealed TargetIDList path during execution.
Consequently, a shortcut can masquerade as a benign link, leading to the launch of a completely different program.
Furthermore, the vulnerabilities revealed by Beukema leverage other default behaviors triggered by inconsistent metadata. When an EnvironmentVariableDataBlock is present but doesn’t align with the LinkTargetIDList, Windows executes the program specified in the LinkInfo structure, even as it continues to show the Environment Variable path.
A variation of this exploit involves providing only the ANSI target value and omitting the corresponding Unicode field. This action causes Explorer to interpret the data as contradictory, leading it to display a distinct path from the LinkTargetIDList, render the Target field uneditable, and obscure any arguments. Despite these visual changes, the hidden ANSI path is ultimately executed.
Cumulatively, these functionalities could empower attackers to falsify the apparent target, obscure the true destination, and trick users into initiating unauthorized applications.
Obscured Command-Line Parameters
Apart from target spoofing, Beukema also showcased a method to embed and conceal malicious command-line instructions within legitimate executable files. This allows LNK files to invoke trusted Windows binaries, simultaneously delivering attacker-defined commands via hidden arguments. This technique facilitates ‘living-off-the-land’ (LOLBINs) execution, bypassing direct links to malware.
The researcher indicated that this is achievable by altering the data fed into specific fields within the LNK file’s “ExtraData” section, which governs supplementary target metadata. Activating the “HasExpString” flag and populating the “EnvironmentVariableDataBlock” with null bytes in its “TargetANSI/TargetUnicode” fields yields what he termed “unforeseen outcomes.”
“Initially, it renders the target field unselectable and read-only,” Beukema explained. “Secondly, it obscures the command-line arguments; however, upon opening the LNK, these arguments are still processed.” This behavior could be exploited to launch a seemingly innocuous system component while surreptitiously executing arbitrary commands, such as downloading malicious payloads or running scripts.
The disclosure suggests that this technique offers a superior advantage to attackers compared to exploiting CVE-2025-9491, primarily because its concealment of visible, padded command lines makes it more challenging to detect.
Beukema observed that this method, akin to the other ones he outlined, leverages Windows’ standard shortcut processing mechanisms rather than identifiable bugs that could be patched. Consequently, effective mitigation largely involves considering untrusted LNK files as inherently risky and restricting user access to them. “Microsoft contends that since user interaction is required without breaching security perimeters, these do not constitute security vulnerabilities,” he stated. “This perspective is not wholly unfounded, as ultimately, many of these issues manifest as user interface inconsistencies.”
This content was originally published by CSO.
