Security advisory

{
  "id": "94ddb01f35f149b952a3b570e97e5b3fbec78c286ec53b7bb0de6159bf5b0556",
  "url": "https://osv.dev/vulnerability/CVE-2021-32842",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2021-32842",
    "summary": "SharpZipLib (or #ziplib) is a Zip, GZip, Tar and BZip2 library. Starting version 1.0.0 and prior to version 1.3.3, a check was added if the destination file is under a destination directory. However, it is not enforced that `_baseDirectory` ends with slash. If the _baseDirectory is not slash terminated like `/home/user/dir` it is possible to create a file with a name thats begins as the destination directory one level up from the directory, i.e. `/home/user/dir.sh`. Because of the file name and destination directory constraints, the arbitrary file creation impact is limited and depends on the use case. Version 1.3.3 fixed this vulnerability.",
    "evidence": "osv:CVE-2021-32842",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2021-32842",
      "aliases": [
        "CVE-2021-32842",
        "GHSA-mm6g-mmq6-53ff"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/icsharpcode/sharpziplib",
              "type": "GIT",
              "events": [
                {
                  "introduced": "fa75398a594b80a8945280ae8e7fb2cf1e7dfa70"
                },
                {
                  "fixed": "1b1ab013ce1df02d8f27cf582197759c614d9126"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:sharpziplib_project:sharpziplib:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "1.0.0"
                      },
                      {
                        "fixed": "1.3.3"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "1b1ab013ce1df02d8f27cf582197759c614d9126"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v1.3.3"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v1.3.2",
            "v1.3.1",
            "v1.3.0",
            "v1.2.0",
            "v1.1.0",
            "v1.0.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-32842.json"
          }
        }
      ],
      "modified": "2026-10-20T10:53:46.295618087Z",
      "provider": "osv",
      "references": [
        "https://github.com/icsharpcode/SharpZipLib/releases/tag/v1.3.3",
        "https://securitylab.github.com/advisories/GHSL-2021-125-sharpziplib/"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2021-32842",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 384604,
  "published_at": "2022-01-26T21:15:13.337+00:00"
}