{"id":"CVE-2026-79775","state":"PUBLISHED","title":"rclone Archive Backend SquashFS Parser Denial of Service","description":"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.","publishedAt":"2026-08-25T15:16:06.427Z","updatedAt":"2026-08-29T11:48:01.347Z","severity":{"score":7.1,"label":"High","version":"4.0","vector":"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","source":"VulnCheck"},"assigner":"VulnCheck","products":["rclone rclone"],"affected":[{"vendor":"rclone","product":"rclone","packageURL":"pkg:golang/github.com/diskfs/go-diskfs","defaultStatus":"unaffected","versions":[{"version":"1.72.0","status":"affected","lessThanOrEqual":"1.74.4","versionType":"semver"}]}],"references":["https://github.com/rclone/rclone/security/advisories/GHSA-6jcg-q3wp-x2f4","https://www.vulncheck.com/advisories/rclone-archive-backend-squashfs-parser-denial-of-service"],"weaknesses":["CWE-129"],"ingestedAt":"2026-10-29T20:13:07.220Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/79xxx/CVE-2026-79775.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-79775","state":"PUBLISHED","datePublished":"2026-08-25T15:16:06.427Z","dateUpdated":"2026-08-29T11:48:01.347Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-08-25T14:29:43.528Z"},"containers":{"cna":{"title":"rclone Archive Backend SquashFS Parser Denial of Service","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"rclone","product":"rclone","packageURL":"pkg:golang/github.com/diskfs/go-diskfs","defaultStatus":"unaffected","versions":[{"version":"1.72.0","status":"affected","lessThanOrEqual":"1.74.4","versionType":"semver"}]}],"references":[{"url":"https://github.com/rclone/rclone/security/advisories/GHSA-6jcg-q3wp-x2f4","tags":["vendor-advisory"],"name":"GitHub Security Advisory (GHSA-6jcg-q3wp-x2f4)"},{"url":"https://www.vulncheck.com/advisories/rclone-archive-backend-squashfs-parser-denial-of-service","name":"VulnCheck Advisory: rclone Archive Backend SquashFS Parser Denial of Service","tags":["third-party-advisory"]}],"metrics":[{"format":"CVSS","cvssV4_0":{"version":"4.0","vectorString":"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","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"LOW","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":7.1,"baseSeverity":"HIGH"}},{"format":"CVSS","cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH","baseScore":6.5,"baseSeverity":"MEDIUM"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-129","lang":"en","description":"Improper Validation of Array Index","type":"CWE"}]}],"providerMetadata":{"shortName":"VulnCheck","orgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateUpdated":"2026-08-29T11:48:01.347Z"},"datePublic":"2026-07-31T00:00:00.000Z","cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:rclone:rclone:-:*:*:*:*:*:*:*"}]}]}],"credits":[{"lang":"en","value":"cyberlanc3r","type":"reporter"},{"lang":"en","value":"ncw","type":"finder"}],"x_generator":{"engine":"vulncheck-endgame"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/rclone/rclone/security/advisories/GHSA-6jcg-q3wp-x2f4","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-25T16:08:04.970845Z","id":"CVE-2026-79775","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-25T16:08:49.589Z"}}]}}}