Vulnerability-Lookup

ubuntu-cve-2026-79775

Vulnerability from osv_ubuntu

Published

2026-08-25 16:17

Modified

2026-09-02 16:27

Summary

Details

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

6.5 (Medium)


                    
                      CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-79775	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-79775	REPORT
	https://github.com/rclone/rclone/security/advisor…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-ncw-rclone-dev",
            "binary_version": "1.36-3ubuntu0.2"
          },
          {
            "binary_name": "rclone",
            "binary_version": "1.36-3ubuntu0.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "rclone",
        "purl": "pkg:deb/ubuntu/rclone@1.36-3ubuntu0.2?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.36-3",
        "1.36-3ubuntu0.1",
        "1.36-3ubuntu0.2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-rclone-rclone-dev",
            "binary_version": "1.50.2-2ubuntu0.2+esm1"
          },
          {
            "binary_name": "rclone",
            "binary_version": "1.50.2-2ubuntu0.2+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "rclone",
        "purl": "pkg:deb/ubuntu/rclone@1.50.2-2ubuntu0.2+esm1?arch=source\u0026distro=esm-apps/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.47.0+ex1-6",
        "1.47.0+ex1-7",
        "1.49.5-2",
        "1.49.5-3",
        "1.50.2-2",
        "1.50.2-2ubuntu0.1",
        "1.50.2-2ubuntu0.2",
        "1.50.2-2ubuntu0.2+esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-rclone-rclone-dev",
            "binary_version": "1.53.3-4ubuntu1.22.04.5+esm1"
          },
          {
            "binary_name": "rclone",
            "binary_version": "1.53.3-4ubuntu1.22.04.5+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:22.04:LTS",
        "name": "rclone",
        "purl": "pkg:deb/ubuntu/rclone@1.53.3-4ubuntu1.22.04.5+esm1?arch=source\u0026distro=esm-apps/jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.53.3-1",
        "1.53.3-2",
        "1.53.3-4",
        "1.53.3-4ubuntu1",
        "1.53.3-4ubuntu1.22.04.1",
        "1.53.3-4ubuntu1.22.04.2",
        "1.53.3-4ubuntu1.22.04.3",
        "1.53.3-4ubuntu1.22.04.3+esm1",
        "1.53.3-4ubuntu1.22.04.4",
        "1.53.3-4ubuntu1.22.04.4+esm1",
        "1.53.3-4ubuntu1.22.04.5",
        "1.53.3-4ubuntu1.22.04.5+esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-rclone-rclone-dev",
            "binary_version": "1.60.1+dfsg-3ubuntu0.24.04.6+esm1"
          },
          {
            "binary_name": "rclone",
            "binary_version": "1.60.1+dfsg-3ubuntu0.24.04.6+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:24.04:LTS",
        "name": "rclone",
        "purl": "pkg:deb/ubuntu/rclone@1.60.1+dfsg-3ubuntu0.24.04.6+esm1?arch=source\u0026distro=esm-apps/noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.60.1+dfsg-2build1",
        "1.60.1+dfsg-3",
        "1.60.1+dfsg-3ubuntu0.24.04.1",
        "1.60.1+dfsg-3ubuntu0.24.04.2",
        "1.60.1+dfsg-3ubuntu0.24.04.3",
        "1.60.1+dfsg-3ubuntu0.24.04.4",
        "1.60.1+dfsg-3ubuntu0.24.04.4+esm1",
        "1.60.1+dfsg-3ubuntu0.24.04.5",
        "1.60.1+dfsg-3ubuntu0.24.04.5+esm1",
        "1.60.1+dfsg-3ubuntu0.24.04.6",
        "1.60.1+dfsg-3ubuntu0.24.04.6+esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-rclone-rclone-dev",
            "binary_version": "1.60.1+dfsg-4ubuntu3.2+esm1"
          },
          {
            "binary_name": "rclone",
            "binary_version": "1.60.1+dfsg-4ubuntu3.2+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:26.04:LTS",
        "name": "rclone",
        "purl": "pkg:deb/ubuntu/rclone@1.60.1+dfsg-4ubuntu3.2+esm1?arch=source\u0026distro=esm-apps/resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.60.1+dfsg-4ubuntu2",
        "1.60.1+dfsg-4ubuntu3",
        "1.60.1+dfsg-4ubuntu3.1",
        "1.60.1+dfsg-4ubuntu3.1+esm1",
        "1.60.1+dfsg-4ubuntu3.2",
        "1.60.1+dfsg-4ubuntu3.2+esm1"
      ]
    }
  ],
  "aliases": [],
  "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": "UBUNTU-CVE-2026-79775",
  "modified": "2026-09-02T16:27:48Z",
  "published": "2026-08-25T16:17:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-79775"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-79775"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/rclone/rclone/security/advisories/GHSA-6jcg-q3wp-x2f4"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "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",
      "type": "CVSS_V4"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-79775"
  ]
}

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

Vulnerability from cvelistv5 – Published: 2026-08-25 15:16 – Updated: 2026-08-29 11:48

Title

rclone Archive Backend SquashFS Parser Denial of Service

Summary

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 mitre root

References

2 references

URL	Tags
https://github.com/rclone/rclone/security/advisor…	vendor-advisory
https://www.vulncheck.com/advisories/rclone-archi…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
rclone	rclone	Affected: 1.72.0 , ≤ 1.74.4 (semver) cpe:2.3:a:rclone:rclone:-:::::::*

Date Public

2026-07-31 00:00

Credits

cyberlanc3r ncw

Show details on NVD website

JSON

To clipboard

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

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.