CVE-2026-118527 in Connect Secure
Summary
by MITRE • 11/03/2026
Use of predictable filenames in Ivanti Connect Secure before versions 25.1.1.3 and 22.8R2.6 allows a remote authenticated attacker to upload files with attacker-controlled content to a known location on disk.
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Analysis
by VulDB Data Team • 11/03/2026
The vulnerability identified as CVE-2024-21893 represents a critical security flaw within Ivanti Connect Secure, specifically affecting versions prior to 25.1.1.3 and the 22.8R2.6 maintenance release. This issue stems from an improper implementation of file handling mechanisms where the system utilizes predictable filenames during the upload process for authenticated users. In secure software design, temporary files or user-uploaded content should be assigned random, unpredictable identifiers to prevent adversaries from anticipating their storage locations on the server's filesystem. By failing to implement such safeguards, Ivanti Connect Secure inadvertently exposes a mechanism that allows remote attackers who have successfully authenticated to the appliance to manipulate file paths and control where uploaded data is persisted.
From a technical perspective, this flaw falls under the category of CWE-377, which describes Insecure Temporary File Creation. The core issue lies in the application's logic for generating filenames or determining storage directories without incorporating sufficient entropy or randomness. When an authenticated user initiates a file upload operation, the system constructs a path based on predictable patterns rather than unique identifiers. This predictability enables an attacker to craft specific requests that direct uploaded content to predetermined locations within the server environment. The ability to write files with attacker-controlled content to known paths significantly escalates the risk profile of this vulnerability beyond simple data leakage or corruption.
The operational impact of this weakness is severe, particularly given its potential for exploitation in conjunction with other vulnerabilities such as CVE-2024-21892 and CVE-2024-21894 to achieve remote code execution without authentication. However, even when exploited by an authenticated attacker, the ability to upload arbitrary files to known locations can lead to significant system compromise. An adversary could overwrite existing configuration files, inject malicious scripts into web-accessible directories, or place backdoors that persist across reboots if proper permissions are not strictly enforced on those specific paths. This capability undermines the integrity of the appliance and can serve as a foothold for further lateral movement within the network infrastructure protected by the VPN gateway.
This vulnerability aligns with MITRE ATT&CK technique T1505.003, Server Software Component: Web Shell, as it facilitates the placement of malicious code on the server that may be executed later to maintain access or execute commands. It also relates to CWE-436, Interpretation Conflict, if the predictable naming leads to ambiguity in how the system processes subsequent requests for those files. The exploitation requires authentication, which limits its scope compared to unauthenticated variants but still poses a substantial threat to organizations that have not yet applied the necessary security patches or implemented compensating controls.
To mitigate this risk, administrators must immediately upgrade Ivanti Connect Secure to version 25.1.1.3 or later, or apply the patch for the 22.8R2.6 branch as specified by Ivanti's official advisories. Until upgrades are performed, organizations should enforce strict network segmentation to limit access to the management interface and VPN portal only from trusted IP addresses using multi-factor authentication where possible. Additionally, implementing file integrity monitoring on critical system directories can help detect unauthorized modifications resulting from this vulnerability. Regular audits of uploaded content handling mechanisms in all enterprise applications are recommended to prevent similar predictable filename issues that could lead to remote code execution or privilege escalation scenarios.