CVE-2026-79775 (GCVE-0-2026-79775)

Vulnerability from cvelistv5 – Published: 2026-08-25 15:16 – Updated: 2026-08-29 11:48
VLAI
Title
rclone Archive Backend SquashFS Parser Denial of Service
Summary
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.
Severity
7.1 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-25 16:08 UTC
CWE
  • CWE-129 - Improper Validation of Array Index
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6182 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
rclone rclone Affected: 1.72.0 , ≤ 1.74.4 (semver)
    cpe:2.3:a:rclone:rclone:-:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-07-31 00:00
Credits
cyberlanc3r ncw
Show details on NVD website
To clipboard 

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