CVE-2026-115724 in VLC for Android
Summary
by MITRE • 10/23/2026
VLC for Android before 3.7.2 contains a confused-deputy file overwrite vulnerability in FileUtils.getUri() that trusts content URIs based only on the com.fsck.k9.attachmentprovider or gmail-ls authority. A co-installed app without permissions can declare these authorities and send a crafted VIEW intent to the exported StartActivity, making VLC write attacker-chosen content under an attacker-chosen name in the shared Download directory, overwriting other apps' files when VLC holds All files access.
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Analysis
by VulDB Data Team • 10/23/2026
The vulnerability identified in versions of VLC for Android prior to 3.7.2 represents a critical confused-deputy flaw within the application's file handling logic, specifically located in the FileUtils.getUri() method. This security defect stems from an insufficient validation mechanism when processing content Uniform Resource Identifiers (URIs). The application incorrectly assumes that any URI possessing specific authority strings, namely com.fsck.k9.attachmentprovider or gmail-ls, is inherently safe and originates from a trusted source. By relying solely on the presence of these authority identifiers without verifying the actual package signature or origin of the app providing the content provider, VLC creates a significant trust boundary violation. This design flaw allows any application installed on the same device to impersonate legitimate email clients that utilize these standard authorities, thereby bypassing the intended security controls designed to restrict file access and manipulation.
From an operational perspective, this vulnerability enables a malicious actor with minimal privileges to execute a sophisticated attack chain involving intent injection and arbitrary file overwriting. An attacker can develop or use a co-installed application that declares one of the targeted authority strings in its manifest. This malicious app then constructs a crafted VIEW intent targeting VLC's exported StartActivity component. When this intent is triggered, it directs VLC to process content from the untrusted source under the guise of being a legitimate email attachment provider. Because VLC holds All files access permissions on modern Android versions, it possesses broad read and write capabilities across the device storage. Consequently, the application proceeds to write data provided by the attacker into the shared Download directory using filenames chosen entirely by the adversary.
The impact of this vulnerability is severe due to its potential for silent file overwriting in a globally accessible location. The shared Download directory is frequently used as a staging ground for files downloaded from various applications and user interactions, making it a high-value target for attackers seeking to compromise system integrity or facilitate further attacks. By overwriting existing files with attacker-controlled content, the vulnerability can lead to data corruption, loss of critical information, or the introduction of malicious payloads into locations where other applications may subsequently read them. This behavior aligns closely with CWE-20 Improper Input Validation and CWE-732 Incorrect Permission Assignment for Critical Resource, as the application fails to validate input sources correctly and grants excessive write privileges based on flawed trust assumptions.
Furthermore, this attack vector is consistent with techniques observed in the MITRE ATT&CK framework, particularly those related to privilege escalation via confused deputy scenarios or unauthorized access through misconfigured permissions. The ability of a low-privileged app to manipulate files owned by or accessible to other apps highlights a failure in enforcing least privilege principles within the application's architecture. To mitigate this risk, developers must implement strict validation checks that verify not only the authority string but also the signing certificate and package name of the provider supplying the content URI. Additionally, restricting file write operations to specific, app-private directories rather than shared public storage would significantly reduce the blast radius of such vulnerabilities. Users are advised to update VLC for Android immediately to version 3.7.2 or later, where these validation checks have been strengthened to prevent unauthorized entities from exploiting this trust relationship and compromising device security through file system manipulation.