CVE-2016-5119 in KeePass
Summary
by MITRE
The automatic update feature in KeePass 2.33 and earlier allows man-in-the-middle attackers to execute arbitrary code by spoofing the version check response and supplying a crafted update.
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Analysis
by VulDB Data Team • 05/14/2026
The vulnerability identified as CVE-2016-5119 represents a critical security flaw in KeePass password manager versions 2.33 and earlier, specifically within its automatic update mechanism. This vulnerability exposes users to significant risk through a man-in-the-middle attack vector that can be exploited by attackers positioned between the user and the legitimate update server. The flaw stems from inadequate validation of update responses, allowing malicious actors to intercept and manipulate version check communications to deliver malicious payloads. The attack scenario typically involves an attacker intercepting network traffic between the KeePass client and its update server, then responding with a forged update notification that appears legitimate to the vulnerable software. This vulnerability directly relates to CWE-347, which addresses the lack of proper authentication and integrity verification mechanisms in security-critical processes. The automatic update feature in KeePass was designed to streamline security maintenance by automatically checking for and applying updates, but this functionality became a security liability due to insufficient cryptographic verification of update sources.
The technical implementation of this vulnerability exploits the trust model inherent in the KeePass update system where the application accepts update information without sufficient validation of the update's authenticity or integrity. When users run KeePass versions 2.33 or earlier, the software performs a routine check against a remote server to determine if newer versions are available. The attacker can intercept this communication and respond with a malicious update package that appears to be a legitimate security patch or feature enhancement. The crafted update can contain malicious code that executes with the privileges of the KeePass process, potentially allowing attackers to gain unauthorized access to stored passwords, modify the password database, or even establish persistent access to the compromised system. This vulnerability operates under the ATT&CK framework's T1068, which covers "Exploitation for Privilege Escalation," and T1133, which addresses "External Remote Services," as it leverages network-based attack vectors to compromise the target system.
The operational impact of CVE-2016-5119 extends beyond simple code execution, as compromised KeePass installations can lead to widespread credential theft and unauthorized system access. Attackers exploiting this vulnerability can target organizations where KeePass is used for password management, potentially gaining access to sensitive corporate credentials stored in the password database. The vulnerability affects not only individual users but also enterprise environments where KeePass might be deployed across multiple systems, amplifying the potential damage. Organizations relying on KeePass for credential management face significant risk of data breaches, as the compromised password manager could provide attackers with access to numerous accounts and systems. The vulnerability's exploitation requires minimal technical skill, making it particularly dangerous as it can be leveraged by threat actors with varying levels of expertise. The attack chain typically involves initial network interception followed by update package manipulation, with the malicious update executing code on the target system without user interaction beyond running the vulnerable KeePass application.
Mitigation strategies for CVE-2016-5119 primarily focus on immediate software updates and network security measures to prevent exploitation. The most effective solution is upgrading to KeePass version 2.34 or later, which includes enhanced update verification mechanisms and cryptographic signature validation. Organizations should implement network monitoring to detect unusual update traffic patterns and establish secure communication channels that prevent man-in-the-middle attacks. Additional protective measures include deploying network segmentation to limit update server access, implementing secure DNS configurations, and using network intrusion detection systems to identify potential exploitation attempts. The vulnerability highlights the importance of maintaining current software versions and implementing proper update validation procedures as outlined in industry best practices such as those recommended by NIST and ISO/IEC 27001. Security teams should also consider implementing application whitelisting policies that restrict execution of unauthorized software updates and establish regular security assessments to identify and remediate similar vulnerabilities in other applications.