rclone up to 1.74.4 SquashFS parser denial of service

Summaryinfo

A vulnerability marked as problematic has been reported in rclone up to 1.74.4. The impacted element is an unknown function of the component SquashFS parser. The manipulation leads to denial of service. This vulnerability is referenced as CVE-2026-79775. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability was found in rclone up to 1.74.4 and classified as problematic. This issue affects an unknown code of the component SquashFS parser. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. The summary by CVE is:

rclone versions >= v1.72.0 and <= v1.74.4 (fixed in v1.75.0) contain multiple denial-of-service vulnerabilities in the archive backend's SquashFS parser, which relies on the github.com/diskfs/go-diskfs dependency. The parser fails to validate attacker-controlled superblock and metadata values before use. An attacker who can place or modify a SquashFS image in storage exposed through an rclone :archive: remote can craft a malicious image that triggers an integer division-by-zero panic (zero block size), an out-of-bounds slice panic (out-of-range inode metadata offset), or a non-progress CPU loop (truncated metadata stream). Variants 1 and 2 terminate the rclone process and, via 'rclone serve sftp', can crash the entire SFTP server; variant 3 causes sustained CPU consumption. Parsing is lazy, so a victim or remote client must address or descend into the malicious archive object to trigger it.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-79775 since 08/25/2026. The exploitation is known to be easy. The attack may be initiated remotely. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

Upgrading to version 1.75.0 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

• rclone

Version

• 1.74.0
• 1.74.1
• 1.74.2
• 1.74.3
• 1.74.4

Website

• Product: https://github.com/rclone/rclone/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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