CVE-2026-43965

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

• https://cna.erlef.org/cves/CVE-2026-43965.html 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
• https://github.com/gleam-lang/gleam/commit/690ca069817bee5f77a28fc3e360627c1da19291 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
• https://github.com/gleam-lang/gleam/security/advisories/GHSA-jqvf-f6p2-wrv3 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
• https://github.com/gleam-lang/gleam/security/advisories/GHSA-jqvf-f6p2-wrv3 134c704f-9b21-4f2e-91b3-4a467353bcc0
• https://osv.dev/vulnerability/EEF-CVE-2026-43965 6b3ad84c-e1a6-4bf7-a703-f496b71e49db

The full cvelistV5 record. Download as CVE-2026-43965.json.

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              "content": {
                "id": "CVE-2026-43965",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-02T15:07:44.667204Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-02T15:08:13.970Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/gleam-lang/gleam/security/advisories/GHSA-jqvf-f6p2-wrv3"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
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          ],
          "vendor": "Gleam",
          "versions": [
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              "status": "affected",
              "version": "v0.18.0-rc1-elixir",
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              "version": "v0.18.0-rc1-node-alpine",
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            },
            {
              "lessThan": "v1.17.0-scratch",
              "status": "affected",
              "version": "v0.18.0-rc1-scratch",
              "versionType": "other"
            }
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      "cpeApplicability": [
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          "nodes": [
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              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:gleam-lang:gleam:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "1.17.0",
                  "versionStartIncluding": "0.18.0-rc1",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
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      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Aly (spect3r1)"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "Abdelrahman Ahmed Aboelkasem (0x2face)"
        },
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "Louis Pilfold"
        },
        {
          "lang": "en",
          "type": "analyst",
          "value": "Jonatan M\u00e4nnchen / EEF"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "<p>Path traversal vulnerability in Gleam's dependency management allows arbitrary directory deletion via malicious <tt>build/packages/packages.toml</tt> content.</p><p>Package keys read from <tt>build/packages/packages.toml</tt> by <tt>LocalPackages::read_from_disc</tt> are passed without validation to <tt>paths.build_packages_package()</tt>, which constructs a filesystem path by joining the project build directory with the attacker-controlled key. The resulting path is then passed to <tt>fs::delete_directory</tt> (which calls <tt>remove_dir_all</tt>). No check is performed to ensure the path remains within the intended <tt>build/packages/</tt> directory. Both absolute paths and relative traversal sequences (e.g. <tt>../</tt>) are accepted as package keys, allowing deletion of arbitrary directories.</p><p>An attacker who can cause a victim to run <tt>gleam deps download</tt> on a project containing a malicious <tt>build/packages/packages.toml</tt> (e.g. by committing the normally-gitignored file to a repository) can cause arbitrary directories on the victim's system to be recursively deleted.</p><p>This issue affects Gleam from 0.18.0-rc1 until 1.17.0.</p>"
            }
          ],
          "value": "Path traversal vulnerability in Gleam's dependency management allows arbitrary directory deletion via malicious build/packages/packages.toml content.\n\nPackage keys read from build/packages/packages.toml by LocalPackages::read_from_disc are passed without validation to paths.build_packages_package(), which constructs a filesystem path by joining the project build directory with the attacker-controlled key. The resulting path is then passed to fs::delete_directory (which calls remove_dir_all). No check is performed to ensure the path remains within the intended build/packages/ directory. Both absolute paths and relative traversal sequences (e.g. ../) are accepted as package keys, allowing deletion of arbitrary directories.\n\nAn attacker who can cause a victim to run gleam deps download on a project containing a malicious build/packages/packages.toml (e.g. by committing the normally-gitignored file to a repository) can cause arbitrary directories on the victim's system to be recursively deleted.\n\nThis issue affects Gleam from 0.18.0-rc1 until 1.17.0."
        }
      ],
      "impacts": [
        {
          "capecId": "CAPEC-139",
          "descriptions": [
            {
              "lang": "en",
              "value": "CAPEC-139 Relative Path Traversal"
            }
          ]
        },
        {
          "capecId": "CAPEC-597",
          "descriptions": [
            {
              "lang": "en",
              "value": "CAPEC-597 Absolute Path Traversal"
            }
          ]
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "LOCAL",
            "baseScore": 5.6,
            "baseSeverity": "MEDIUM",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "ACTIVE",
            "vectorString": "CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-22",
              "description": "CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-02T19:14:19.113Z",
        "orgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
        "shortName": "EEF"
      },
      "references": [
        {
          "tags": [
            "vendor-advisory",
            "related"
          ],
          "url": "https://github.com/gleam-lang/gleam/security/advisories/GHSA-jqvf-f6p2-wrv3"
        },
        {
          "tags": [
            "related"
          ],
          "url": "https://cna.erlef.org/cves/CVE-2026-43965.html"
        },
        {
          "tags": [
            "related"
          ],
          "url": "https://osv.dev/vulnerability/EEF-CVE-2026-43965"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/gleam-lang/gleam/commit/690ca069817bee5f77a28fc3e360627c1da19291"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "Path Traversal in build/packages/packages.toml Allows Arbitrary Directory Deletion",
      "x_generator": {
        "engine": "cvelib 1.8.0"
      }
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  },
  "cveMetadata": {
    "assignerOrgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
    "assignerShortName": "EEF",
    "cveId": "CVE-2026-43965",
    "datePublished": "2026-06-02T13:41:37.421Z",
    "dateReserved": "2026-05-04T18:23:25.573Z",
    "dateUpdated": "2026-06-02T19:14:19.113Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}