CVE-2005-2368 in vim
Summary
by MITRE
vim 6.3 before 6.3.082, with modelines enabled, allows external user-assisted attackers to execute arbitrary commands via shell metacharacters in the (1) glob or (2) expand commands of a foldexpr expression for calculating fold levels.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 06/30/2025
The vulnerability described in CVE-2005-2368 represents a critical command injection flaw in the vim text editor version 6.3 and earlier, specifically when modelines are enabled. This vulnerability resides in the foldexpr expression handling mechanism, which is used to calculate fold levels in vim's folding feature. When vim processes fold expressions, it evaluates them as part of the document rendering process, creating a potential attack surface where malicious input can be executed as shell commands. The flaw manifests when the glob or expand commands within foldexpr expressions contain shell metacharacters that are not properly sanitized or escaped, allowing attackers to inject arbitrary shell commands that get executed with the privileges of the user running vim. This vulnerability operates under the CWE-78 principle of improper neutralization of special elements used in OS commands, specifically targeting the command execution pathways within vim's fold handling system. The attack vector is user-assisted, meaning an attacker must convince a victim to open a malicious file containing crafted fold expressions, making this a social engineering component to the exploit.
The technical implementation of this vulnerability exploits the interaction between vim's modeline processing and its fold expression evaluation engine. When vim encounters a modeline in a file, it parses the line to configure editor settings, including fold expressions that determine how the document should be folded. The glob command in vim's expression evaluation can be used to expand wildcards, while the expand command can be used to expand special variables, both of which can accept shell metacharacters. When these commands are used within foldexpr expressions and contain unescaped shell special characters such as semicolons, ampersands, or backticks, they can be interpreted by the underlying shell and executed as part of the fold calculation process. The vulnerability specifically affects the version range before 6.3.082, indicating that this was a targeted issue that was addressed through proper input sanitization and shell escaping mechanisms in the updated version. This type of vulnerability aligns with the ATT&CK technique T1059.001 for command and scripting interpreter, where adversaries use legitimate command-line interfaces to execute malicious code.
The operational impact of CVE-2005-2368 is significant as it allows for remote code execution in the context of the user running vim, potentially leading to full system compromise if the user has elevated privileges. An attacker could craft a malicious file containing a specially crafted fold expression that, when opened by a victim, would execute commands such as system shell commands, file manipulation, or network communication. The vulnerability is particularly dangerous because it can be triggered simply by opening a file, without requiring any special actions from the user beyond normal text editing operations. The attack could be delivered through various vectors including email attachments, shared network drives, or web-based file sharing systems. Organizations using older versions of vim without proper patching would be at risk, especially in environments where users frequently open files from untrusted sources. The vulnerability also demonstrates the broader security implications of text editors that process untrusted input with shell command execution capabilities, highlighting the need for proper input validation and sandboxing mechanisms in such applications. This flaw underscores the importance of keeping software updated and implementing proper security controls when handling potentially malicious content, as the vulnerability can be exploited in environments where users may inadvertently open compromised files.