GHSA-HQQ5-M7FP-MQC3
Vulnerability from github – Published: 2026-08-25 18:31 – Updated: 2026-08-25 18:31rclone 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.
{
"affected": [],
"aliases": [
"CVE-2026-79775"
],
"database_specific": {
"cwe_ids": [
"CWE-129"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-25T16:17:29Z",
"severity": "HIGH"
},
"details": "rclone versions \u003e= v1.72.0 and \u003c= v1.74.4 (fixed in v1.75.0) contain multiple denial-of-service vulnerabilities in the archive backend\u0027s 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 \u0027rclone serve sftp\u0027, 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.",
"id": "GHSA-hqq5-m7fp-mqc3",
"modified": "2026-08-25T18:31:54Z",
"published": "2026-08-25T18:31:54Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/rclone/rclone/security/advisories/GHSA-6jcg-q3wp-x2f4"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-79775"
},
{
"type": "WEB",
"url": "https://www.vulncheck.com/advisories/rclone-archive-backend-squashfs-parser-denial-of-service"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
},
{
"score": "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
Sightings
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|---|
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