Critical GNU Wget2 Vulnerability Exposes Systems to Remote File Overwrite Attacks
A significant security flaw has been identified in GNU Wget2, a widely utilized command-line tool for downloading files from the internet. This vulnerability, designated as CVE-2025-69194, enables remote attackers to overwrite arbitrary files on a victim’s system, potentially leading to data loss or complete system compromise.
Understanding the Vulnerability
The root of this vulnerability lies in the improper validation of file paths within Metalink documents processed by Wget2. Metalink is a format that provides information about download locations and file checksums. By crafting malicious Metalink files containing path traversal sequences, attackers can deceive Wget2 into writing files to unintended locations on the filesystem.
When a user downloads and processes a weaponized Metalink document, Wget2 fails to adequately sanitize the file paths in the metadata. This oversight allows attackers to specify arbitrary locations for file writing, constrained only by the permissions of the user executing Wget2.
Technical Details
– CVE ID: CVE-2025-69194
– Severity: Important / High
– CVSS Score: 8.8
– Weakness: CWE-22: Path Traversal
According to the Common Weakness Enumeration (CWE-22), this path traversal flaw can have multiple severe consequences. Attackers may overwrite critical system files, programs, or libraries used for code execution. They could modify security configuration files to bypass authentication mechanisms or create backdoor accounts.
In some scenarios, attackers may read sensitive files by directing Wget2 to copy them to accessible locations. Red Hat has classified this vulnerability as of Important severity, noting that while it requires user interaction to process the malicious Metalink file, exploitation can realistically lead to local code execution or data corruption.
The vulnerability can also cause denial-of-service attacks by corrupting or deleting essential system files. Currently, no complete mitigation is available that meets enterprise deployment standards.
Potential Impact
The implications of this vulnerability are far-reaching:
– Data Integrity Risks: Attackers can overwrite or delete critical system files, leading to data corruption or loss.
– System Compromise: By overwriting executable files or libraries, attackers can introduce malicious code, potentially gaining control over the affected system.
– Security Configuration Alteration: Modification of security-related files can disable protective measures, making systems more susceptible to further attacks.
– Denial-of-Service (DoS): Corruption or deletion of essential files can render systems inoperable, disrupting services and operations.
Mitigation Strategies
Given the severity of this vulnerability, immediate action is essential:
1. Avoid Untrusted Metalink Files: Users should refrain from processing Metalink files from unverified or untrusted sources.
2. Monitor for Security Updates: Stay vigilant for security patches and updates from the GNU Wget2 project.
3. Implement Network Controls: Organizations should assess their exposure and implement network-level controls to limit potential exploitation until patches become widely available.
4. User Education: Educate users about the risks associated with downloading and processing files from untrusted sources.
Conclusion
The discovery of CVE-2025-69194 in GNU Wget2 underscores the critical importance of input validation and the potential risks associated with processing external files. Users and administrators must exercise caution and implement recommended mitigation strategies to protect their systems from potential exploitation.
