CVE-2026-74975 in Firefox
Summary
by MITRE • 08/18/2026
Spoofing issue in the Downloads component in Firefox for Android. This vulnerability was fixed in Firefox 154.
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Analysis
by VulDB Data Team • 08/18/2026
The identified security flaw resides within the download management subsystem of Mozilla Firefox on the Android platform, specifically involving a spoofing vulnerability that undermines user trust and system integrity. In this context, the term spoofing refers to an attack vector where malicious actors deceive users by presenting fake or misleading information regarding downloaded files. This typically manifests through manipulated file names, deceptive icons, or fabricated metadata that makes a potentially harmful executable appear as a benign document such as a PDF or image file. The core technical failure lies in how the browser handles and displays download notifications and final file representations to the end-user interface without sufficient validation of the source content against its declared type or origin. By exploiting this discrepancy between actual file content and displayed attributes, an attacker can trick users into executing malicious payloads under false pretenses, effectively bypassing user caution mechanisms that rely on visual cues for risk assessment.
From a technical perspective, this vulnerability highlights deficiencies in input validation and output encoding within the Android-specific implementation of Firefox's download handler. When a resource is fetched from a remote server, the browser must accurately map HTTP headers such as Content-Disposition or MIME types to local file attributes while ensuring that these mappings cannot be trivially forged by an untrusted source. The flaw suggests that the application fails to enforce strict type checking or sanitization of display strings before rendering them in the notification shade or download manager UI. This allows for a classic case of user interface deception, where the boundary between trusted browser behavior and malicious input is blurred due to insufficient separation of data from presentation logic. Such oversights are particularly dangerous on mobile operating systems like Android, where users frequently interact with downloaded files directly through third-party apps that may execute code based solely on file extensions or perceived safety ratings derived from user interface labels.
The operational impact of this vulnerability extends beyond simple malware execution to include broader threats such as credential theft and persistent device compromise. If a user is successfully spoofed into downloading and opening a malicious application disguised as a legitimate utility, the resulting infection can lead to data exfiltration, unauthorized access to sensitive personal information stored on the device, or even full remote control of the Android system depending on the capabilities of the payload. Furthermore, this type of vulnerability erodes the fundamental trust model of web browsers, which rely heavily on user awareness and correct interpretation of security indicators. When users cannot reliably distinguish between safe and unsafe downloads based on browser-provided information, their overall security posture deteriorates significantly, making them more susceptible to social engineering attacks that complement technical exploits.
In terms of industry classification standards, this vulnerability aligns closely with CWE-20 Improper Input Validation and CWE-798 Use of Hard-coded Credentials if the spoofing involves impersonating trusted sources through static identifiers. More specifically, it falls under the domain of UI Redressing or Spoofing as defined in Common Weakness Enumerations related to deceptive interfaces. Within the MITRE ATT&CK framework for mobile platforms, this behavior corresponds to techniques involving Masquerading and User Execution, where adversaries disguise malicious artifacts to evade detection and rely on user interaction to achieve initial access. The attack chain typically involves delivering a lure via web content or email that prompts the download of the spoofed file, followed by social engineering elements that encourage immediate execution without verification.
To mitigate this risk, users are strongly advised to update their Firefox application immediately to version 154 or later, where these specific flaws in the downloads component have been addressed through improved validation logic and enhanced display sanitization protocols. Security best practices also dictate enabling automatic updates for all mobile applications to ensure timely patching of such vulnerabilities as they are discovered by vendors. Additionally, users should exercise caution when downloading files from untrusted sources, verifying file integrity using checksums where available, and reviewing app permissions before installation. Browser security settings can be configured to prompt for confirmation on certain types of downloads or to block automatic execution of downloaded files until explicitly approved by the user, thereby adding an additional layer of defense against spoofing attempts that rely on passive user behavior.