CVE-2018-11248 in FileDownloader
Summary
by MITRE
util/FileDownloadUtils.java in FileDownloader 1.7.3 does not check an attachment's name. If an attacker places "../" in the file name, the file can be stored in an unintended directory because of Directory Traversal.
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Analysis
by VulDB Data Team • 03/14/2023
The vulnerability identified as CVE-2018-11248 resides within the FileDownloader 1.7.3 software suite, specifically in the util/FileDownloadUtils.java component. This flaw represents a classic directory traversal attack vector that exploits insufficient input validation mechanisms. The vulnerability manifests when the application processes file attachments without properly sanitizing or validating the filename parameter, creating an opportunity for malicious actors to manipulate the file storage destination through crafted input sequences.
The technical implementation of this vulnerability stems from the absence of proper path validation checks within the file download utility. When an attacker supplies a filename containing directory traversal sequences such as "../", the application fails to sanitize this input before attempting to store the file. This omission allows the system to interpret the traversal sequences and write files to unintended directories outside the intended storage location. The flaw directly maps to CWE-22, which categorizes improper limitation of a pathname to a restricted directory, commonly known as path traversal or directory traversal vulnerabilities.
The operational impact of this vulnerability extends beyond simple unauthorized file placement, as it provides attackers with potential access to critical system resources and sensitive data. An attacker could leverage this vulnerability to overwrite existing system files, create malicious files in system directories, or potentially execute arbitrary code if the application has elevated privileges. The vulnerability also poses significant risks to data integrity and system confidentiality, as it enables unauthorized modification of files that should remain protected within designated storage areas.
Security professionals should consider this vulnerability in the context of the ATT&CK framework, particularly under the techniques related to privilege escalation and persistence. The vulnerability can be exploited as part of a broader attack chain where initial access leads to directory traversal, enabling attackers to establish persistence mechanisms or escalate privileges within the target environment. Organizations using FileDownloader 1.7.3 should implement immediate mitigations including input validation, proper path sanitization, and strict file naming conventions to prevent exploitation. The recommended approach involves implementing comprehensive validation checks that reject filenames containing directory traversal sequences, enforcing strict access controls on file storage directories, and conducting regular security audits to identify similar vulnerabilities in other components of the application stack.