Vulnerability-Lookup

UBUNTU-CVE-2026-53801 (CVE-2026-53801)

Vulnerability from osv_ubuntu – Published: 2026-08-13 15:19 – Updated: 2026-08-19 11:06 – Source website

Details

rsync before 3.5.0 contains a symlink race condition vulnerability in the sender's directory scanning logic that allows attackers to cause the sender to enumerate and transfer files outside the module root's intended subtree. Attackers who can create or manipulate symlinks in a path component of the scanned tree can replace a symlink with a directory entry pointing outside the module root between the lstat() call and the subsequent opendir() call, exposing files beyond the intended root in both daemon-mode and non-daemon sender-side scanning.

Severity

5.9 (Medium)


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

8.2 (High)


                    
                      CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-53801	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-53801	REPORT
	https://download.samba.org/pub/rsync/NEWS#3.5.0	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "rsync",
            "binary_version": "3.1.0-2ubuntu0.4+esm4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "rsync",
        "purl": "pkg:deb/ubuntu/rsync@3.1.0-2ubuntu0.4+esm4?arch=source\u0026distro=esm-infra-legacy/trusty"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.0.9-4ubuntu1",
        "3.1.0-2",
        "3.1.0-2ubuntu0.1",
        "3.1.0-2ubuntu0.2",
        "3.1.0-2ubuntu0.3",
        "3.1.0-2ubuntu0.4",
        "3.1.0-2ubuntu0.4+esm1",
        "3.1.0-2ubuntu0.4+esm2",
        "3.1.0-2ubuntu0.4+esm3",
        "3.1.0-2ubuntu0.4+esm4"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "rsync",
            "binary_version": "3.1.1-3ubuntu1.3+esm6"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "rsync",
        "purl": "pkg:deb/ubuntu/rsync@3.1.1-3ubuntu1.3+esm6?arch=source\u0026distro=esm-infra-legacy/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.1.1-3",
        "3.1.1-3ubuntu1",
        "3.1.1-3ubuntu1.1",
        "3.1.1-3ubuntu1.2",
        "3.1.1-3ubuntu1.3",
        "3.1.1-3ubuntu1.3+esm1",
        "3.1.1-3ubuntu1.3+esm2",
        "3.1.1-3ubuntu1.3+esm3",
        "3.1.1-3ubuntu1.3+esm4",
        "3.1.1-3ubuntu1.3+esm5",
        "3.1.1-3ubuntu1.3+esm6"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "rsync",
            "binary_version": "3.1.2-2.1ubuntu1.6+esm4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "rsync",
        "purl": "pkg:deb/ubuntu/rsync@3.1.2-2.1ubuntu1.6+esm4?arch=source\u0026distro=esm-infra/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.1.2-2",
        "3.1.2-2.1",
        "3.1.2-2.1ubuntu1",
        "3.1.2-2.1ubuntu1.1",
        "3.1.2-2.1ubuntu1.2",
        "3.1.2-2.1ubuntu1.3",
        "3.1.2-2.1ubuntu1.4",
        "3.1.2-2.1ubuntu1.5",
        "3.1.2-2.1ubuntu1.6",
        "3.1.2-2.1ubuntu1.6+esm1",
        "3.1.2-2.1ubuntu1.6+esm2",
        "3.1.2-2.1ubuntu1.6+esm3",
        "3.1.2-2.1ubuntu1.6+esm4"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "rsync",
            "binary_version": "3.1.3-8ubuntu0.9+esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "rsync",
        "purl": "pkg:deb/ubuntu/rsync@3.1.3-8ubuntu0.9+esm2?arch=source\u0026distro=esm-infra/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.1.3-6",
        "3.1.3-8",
        "3.1.3-8ubuntu0.1",
        "3.1.3-8ubuntu0.2",
        "3.1.3-8ubuntu0.3",
        "3.1.3-8ubuntu0.4",
        "3.1.3-8ubuntu0.5",
        "3.1.3-8ubuntu0.7",
        "3.1.3-8ubuntu0.8",
        "3.1.3-8ubuntu0.9",
        "3.1.3-8ubuntu0.9+esm1",
        "3.1.3-8ubuntu0.9+esm2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "rsync",
            "binary_version": "3.2.7-0ubuntu0.22.04.7"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "rsync",
        "purl": "pkg:deb/ubuntu/rsync@3.2.7-0ubuntu0.22.04.7?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.2.3-4ubuntu1",
        "3.2.3-4ubuntu2",
        "3.2.3-8ubuntu1",
        "3.2.3-8ubuntu2",
        "3.2.3-8ubuntu3",
        "3.2.3-8ubuntu3.1",
        "3.2.7-0ubuntu0.22.04.2",
        "3.2.7-0ubuntu0.22.04.3",
        "3.2.7-0ubuntu0.22.04.4",
        "3.2.7-0ubuntu0.22.04.6",
        "3.2.7-0ubuntu0.22.04.7"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "rsync",
            "binary_version": "3.2.7-1ubuntu1.5"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "rsync",
        "purl": "pkg:deb/ubuntu/rsync@3.2.7-1ubuntu1.5?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.2.7-1",
        "3.2.7-1build1",
        "3.2.7-1build2",
        "3.2.7-1ubuntu1",
        "3.2.7-1ubuntu1.1",
        "3.2.7-1ubuntu1.2",
        "3.2.7-1ubuntu1.4",
        "3.2.7-1ubuntu1.5"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "rsync",
            "binary_version": "3.4.1+ds1-7ubuntu0.3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "rsync",
        "purl": "pkg:deb/ubuntu/rsync@3.4.1+ds1-7ubuntu0.3?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.4.1+ds1-5ubuntu1",
        "3.4.1+ds1-6",
        "3.4.1+ds1-7",
        "3.4.1+ds1-7ubuntu0.2",
        "3.4.1+ds1-7ubuntu0.3"
      ]
    }
  ],
  "aliases": [],
  "details": "rsync before 3.5.0\u00a0contains a symlink race condition vulnerability in the sender\u0027s directory scanning logic that allows attackers to cause the sender to enumerate and transfer files outside the module root\u0027s intended subtree. Attackers who can create or manipulate symlinks in a path component of the scanned tree can replace a symlink with a directory entry pointing outside the module root between the lstat() call and the subsequent opendir() call, exposing files beyond the intended root in both daemon-mode and non-daemon sender-side scanning.",
  "id": "UBUNTU-CVE-2026-53801",
  "modified": "2026-08-19T11:06:28Z",
  "published": "2026-08-13T15:19:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-53801"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-53801"
    },
    {
      "type": "REPORT",
      "url": "https://download.samba.org/pub/rsync/NEWS#3.5.0"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-53801"
  ]
}

CVE-2026-53801 (GCVE-0-2026-53801)

Vulnerability from cvelistv5 – Published: 2026-08-13 14:41 – Updated: 2026-08-14 16:50

Title

rsync < 3.5.0 Symlink Race Condition Directory Traversal

Summary

Severity

8.2 (High)


                        
                          CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

5.9 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-14 15:51 UTC

CWE

CWE-59 - Improper Link Resolution Before File Access ('Link Following')
CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition

Assigner

VulnCheck mitre root

References

3 references

URL	Tags
https://github.com/RsyncProject/rsync/security/ad…	vendor-advisory
https://github.com/RsyncProject/rsync/releases/ta…	release-notes
https://www.vulncheck.com/advisories/rsync-symlin…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
RsyncProject	rsync	Affected: 0 , ≤ 3.4.4 (semver) Unaffected: 3.5.0 (semver) cpe:2.3:a:samba:rsync::::::::

Date Public

2026-08-12 00:00

Show details on NVD website

JSON

To clipboard

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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.