CVE-2026-51400 in Vim
Summary
by MITRE • 08/05/2026
An issue in Vim Project v9.2.0389 and earlier allows a local attacker to execute arbitrary code via the vms_fixfilename() function within file vim/src/os_vms.c
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Analysis
by VulDB Data Team • 08/05/2026
The vulnerability resides within the Vim text editor project version 9.2.0389 and earlier, specifically in the vms_fixfilename() function located in the file vim/src/os_vms.c. This represents a critical security flaw that enables local attackers to execute arbitrary code on affected systems. The issue stems from improper input validation and handling within the filename processing logic on VMS (Virtual Memory System) platforms, creating an avenue for privilege escalation and code injection attacks.
The technical implementation of this vulnerability involves the vms_fixfilename() function failing to properly sanitize or validate user-supplied filename inputs before processing them through system calls. When a malicious actor provides crafted input to Vim, particularly during file operations such as opening, saving, or manipulating files, the function processes these inputs without adequate boundary checks or validation mechanisms. This creates a buffer overflow condition or command injection vulnerability that can be exploited to execute malicious code with the privileges of the user running Vim.
From an operational perspective, this vulnerability poses significant risks to systems where Vim is installed and used for file operations. Attackers can leverage this flaw to gain unauthorized access to system resources, potentially leading to complete system compromise. The local nature of the attack means that exploitation requires physical or remote access to the target system, but once successful, the attacker can execute code with the same privileges as the vulnerable Vim process. This vulnerability directly impacts the principle of least privilege and can serve as a foothold for further lateral movement within network environments.
The vulnerability can be categorized under CWE-121 as a stack-based buffer overflow or CWE-78 as a command injection flaw, both of which are well-documented in the Common Weakness Enumeration catalog. From an ATT&CK framework perspective, this vulnerability maps to T1059.006 for command and scripting interpreter usage, and potentially T1068 for exploit for privilege escalation. The attack surface is particularly concerning given Vim's widespread use across Unix-like systems and its integration into various development environments, making it a prime target for attackers seeking persistent access.
Mitigation strategies should include immediate patching of affected Vim installations to version 9.2.0390 or later where this vulnerability has been resolved. System administrators should also implement restrictive file permissions on Vim installations and monitor for unusual file operations that might indicate exploitation attempts. Additional protective measures include employing sandboxing techniques, restricting user privileges when running Vim, and implementing network segmentation to limit the potential impact of successful exploitation. Organizations should also consider deploying intrusion detection systems that can identify suspicious command execution patterns associated with this type of vulnerability.