Vulnerability-Lookup

GHSA-H444-6J9X-P8VH

Vulnerability from github – Published: 2026-07-06 20:24 – Updated: 2026-07-06 20:24

Summary

mv: symlinks expanded during cross-device move (resource exhaustion / data duplication)

Details

When moving directories across filesystems, uutils mv dereferences symlinks inside the tree, copying their targets as real files/dirs instead of preserving the symlinks. GNU preserves symlinks by default. E.g. a etc_link -> /etc inside the source becomes a full copy of /etc at the destination.

Impact: (1) resource exhaustion — a small tree can expand into a huge copy (time/disk DoS); (2) unintended duplication of sensitive paths referenced by symlink; (3) symlink-loop amplification causing deep recursion. Recommendation: in cross-device fallback, detect symlinks via symlink_metadata() and recreate with read_link()/symlink(); add loop detection.

Remediation: Acknowledged by Canonical; fixed in commit 9654e4ab.

Reported by Zellic in the uutils coreutils Program Security Assessment (prepared for Canonical, Jan 20 2026), audited commit 3a07ffc5a9bd4c283e75afa548ba1f1957bad242. Finding 3.63. Credit: Zellic.

Severity

6.6 (Medium)


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

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JSON

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{
  "affected": [
    {
      "package": {
        "ecosystem": "crates.io",
        "name": "uu_mv"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.7.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-35365"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400",
      "CWE-59"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-07-06T20:24:53Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "When moving directories across filesystems, uutils `mv` dereferences symlinks inside the tree, copying their targets as real files/dirs instead of preserving the symlinks. GNU preserves symlinks by default. E.g. a `etc_link -\u003e /etc` inside the source becomes a full copy of `/etc` at the destination.\n\n**Impact:** (1) resource exhaustion \u2014 a small tree can expand into a huge copy (time/disk DoS); (2) unintended duplication of sensitive paths referenced by symlink; (3) symlink-loop amplification causing deep recursion. Recommendation: in cross-device fallback, detect symlinks via `symlink_metadata()` and recreate with `read_link()`/`symlink()`; add loop detection.\n\n**Remediation:** Acknowledged by Canonical; fixed in commit 9654e4ab.\n\n---\n_Reported by Zellic in the *uutils coreutils Program Security Assessment* (prepared for Canonical, Jan 20 2026), audited commit `3a07ffc5a9bd4c283e75afa548ba1f1957bad242`. Finding 3.63. Credit: Zellic._",
  "id": "GHSA-h444-6j9x-p8vh",
  "modified": "2026-07-06T20:24:53Z",
  "published": "2026-07-06T20:24:53Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/uutils/coreutils/security/advisories/GHSA-h444-6j9x-p8vh"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-35365"
    },
    {
      "type": "WEB",
      "url": "https://github.com/uutils/coreutils/pull/10546"
    },
    {
      "type": "WEB",
      "url": "https://github.com/uutils/coreutils/commit/9654e4abaf24449ef2279e9a16963edb5c8b8fef"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/uutils/coreutils"
    },
    {
      "type": "WEB",
      "url": "https://github.com/uutils/coreutils/releases/tag/0.7.0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "mv: symlinks expanded during cross-device move (resource exhaustion / data duplication)"
}

CVE-2026-35365 (GCVE-0-2026-35365)

Vulnerability from cvelistv5 – Published: 2026-04-22 16:08 – Updated: 2026-04-22 17:59

Title

uutils coreutils mv Denial of Service and Data Duplication via Improper Symlink Expansion

Summary

The mv utility in uutils coreutils improperly handles directory trees containing symbolic links during moves across filesystem boundaries. Instead of preserving symlinks, the implementation expands them, copying the linked targets as real files or directories at the destination. This can lead to resource exhaustion (disk space or time) if symlinks point to large external directories, unexpected duplication of sensitive data into unintended locations, or infinite recursion and repeated copying in the presence of symlink loops.

Severity

6.6 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-22 17:59 UTC

CWE

CWE-59 - Improper Link Resolution Before File Access ('Link Following')

Assigner

canonical mitre root Scorecard

References

2 references

URL	Tags
https://github.com/uutils/coreutils/pull/10546	issue-trackingpatch
https://github.com/uutils/coreutils/releases/tag/0.7.0	vendor-advisory

Impacted products

1 product

Vendor	Product	Version
Uutils	coreutils	Affected: 0 , < 0.7.0 (semver)

Credits

Zellic

Show details on NVD website

JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-35365",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-22T17:59:28.819706Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-22T17:59:34.571Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://github.com/uutils",
          "defaultStatus": "unaffected",
          "packageName": "coreutils",
          "platforms": [
            "Linux",
            "Unix",
            "macOS"
          ],
          "product": "coreutils",
          "repo": "https://github.com/uutils/coreutils",
          "vendor": "Uutils",
          "versions": [
            {
              "lessThan": "0.7.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Zellic"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "The mv utility in uutils coreutils improperly handles directory trees containing symbolic links during moves across filesystem boundaries. Instead of preserving symlinks, the implementation expands them, copying the linked targets as real files or directories at the destination. This can lead to resource exhaustion (disk space or time) if symlinks point to large external directories, unexpected duplication of sensitive data into unintended locations, or infinite recursion and repeated copying in the presence of symlink loops."
        }
      ],
      "impacts": [
        {
          "capecId": "CAPEC-132",
          "descriptions": [
            {
              "lang": "en",
              "value": "CAPEC-132: Symlink Attack"
            }
          ]
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "LOCAL",
            "availabilityImpact": "LOW",
            "baseScore": 6.6,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-59",
              "description": "CWE-59: Improper Link Resolution Before File Access (\u0027Link Following\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-22T16:08:41.136Z",
        "orgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc",
        "shortName": "canonical"
      },
      "references": [
        {
          "tags": [
            "issue-tracking",
            "patch"
          ],
          "url": "https://github.com/uutils/coreutils/pull/10546"
        },
        {
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://github.com/uutils/coreutils/releases/tag/0.7.0"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "uutils coreutils mv Denial of Service and Data Duplication via Improper Symlink Expansion"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc",
    "assignerShortName": "canonical",
    "cveId": "CVE-2026-35365",
    "datePublished": "2026-04-22T16:08:41.136Z",
    "dateReserved": "2026-04-02T12:58:56.088Z",
    "dateUpdated": "2026-04-22T17:59:34.571Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

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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.

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.
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GHSA-H444-6J9X-P8VH

CVE-2026-35365 (GCVE-0-2026-35365)

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