Security advisory

{
  "id": "38252fa4e95ea6c79cc47f3b134dbb8f7ab0197a7c4e4dff926acd66392669a5",
  "url": "https://osv.dev/vulnerability/CVE-2023-27535",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2023-27535",
    "summary": "An authentication bypass vulnerability exists in libcurl <8.0.0 in the FTP connection reuse feature that can result in wrong credentials being used during subsequent transfers. Previously created connections are kept in a connection pool for reuse if they match the current setup. However, certain FTP settings such as CURLOPT_FTP_ACCOUNT, CURLOPT_FTP_ALTERNATIVE_TO_USER, CURLOPT_FTP_SSL_CCC, and CURLOPT_USE_SSL were not included in the configuration match checks, causing them to match too easily. This could lead to libcurl using the wrong credentials when performing a transfer, potentially allowing unauthorized access to sensitive information.",
    "evidence": "osv:CVE-2023-27535",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2023-27535",
      "aliases": [
        "CURL-CVE-2023-27535",
        "CVE-2023-27535"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/curl/curl",
              "type": "GIT",
              "events": [
                {
                  "introduced": "4a9e12542dba5d3ce4b6205f1ec58e1336bc4b0e"
                },
                {
                  "last_affected": "046209e561b7e9b5aab1aef7daebf29ee6e6e8c7"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:haxx:libcurl:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "7.13.0"
                      },
                      {
                        "last_affected": "7.88.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "curl-7_88_1",
            "curl-7_88_0",
            "curl-7_87_0",
            "curl-7_86_0",
            "curl-7_85_0",
            "curl-7_84_0",
            "curl-7_83_1",
            "curl-7_83_0",
            "curl-7_82_0",
            "curl-7_81_0",
            "curl-7_80_0",
            "curl-7_79_1",
            "curl-7_79_0",
            "curl-7_78_0",
            "curl-7_77_0",
            "curl-7_76_1",
            "curl-7_76_0",
            "curl-7_75_0",
            "curl-7_74_0",
            "curl-7_73_0",
            "curl-7_72_0",
            "curl-7_71_1",
            "curl-7_71_0",
            "curl-7_70_0",
            "curl-7_69_1",
            "curl-7_69_0",
            "curl-7_68_0",
            "curl-7_67_0",
            "curl-7_66_0",
            "curl-7_65_3",
            "curl-7_65_2",
            "curl-7_65_1",
            "curl-7_65_0",
            "curl-7_64_1",
            "curl-7_64_0",
            "curl-7_63_0",
            "curl-7_62_0",
            "curl-7_61_1",
            "curl-7_61_0",
            "curl-7_60_0",
            "curl-7_59_0",
            "curl-7_58_0",
            "curl-7_57_0",
            "curl-7_56_1",
            "curl-7_56_0",
            "curl-7_55_1",
            "curl-7_55_0",
            "curl-7_54_1",
            "curl-7_54_0",
            "curl-7_53_1",
            "curl-7_53_0",
            "curl-7_52_1",
            "curl-7_52_0",
            "curl-7_51_0",
            "curl-7_50_3",
            "curl-7_50_2",
            "curl-7_50_1",
            "curl-7_50_0",
            "curl-7_49_1",
            "curl-7_49_0",
            "curl-7_48_0",
            "curl-7_47_1",
            "curl-7_47_0",
            "curl-7_46_0",
            "curl-7_45_0",
            "curl-7_44_0",
            "curl-7_43_0",
            "curl-7_42_0",
            "curl-7_41_0",
            "curl-7_40_0",
            "curl-7_39_0",
            "curl-7_38_0",
            "curl-7_37_1",
            "curl-7_37_0",
            "curl-7_36_0",
            "curl-7_35_0",
            "curl-7_34_0",
            "curl-7_33_0",
            "curl-7_32_0",
            "curl-7_31_0",
            "curl-7_30_0",
            "curl-7_29_0",
            "curl-7_28_1",
            "curl-7_28_0",
            "curl-7_27_0",
            "curl-7_26_0",
            "curl-7_25_0",
            "curl-7_23_1",
            "curl-7_23_0",
            "curl-7_22_0",
            "curl-7_21_7",
            "curl-7_21_6",
            "curl-7_21_5",
            "curl-7_21_4",
            "curl-7_21_3",
            "curl-7_21_2",
            "curl-7_21_1",
            "curl-7_21_0",
            "curl-7_20_1",
            "curl-7_20_0",
            "curl-7_19_7",
            "curl-7_19_6",
            "curl-7_19_5",
            "curl-7_19_4",
            "curl-7_19_3",
            "curl-7_19_2",
            "curl-7_19_1",
            "curl-7_19_0",
            "curl-7_18_2",
            "curl-7_18_1",
            "curl-7_18_0",
            "curl-7_17_1",
            "curl-7_17_0",
            "curl-7_17_0-preldapfix",
            "curl-7_16_4",
            "curl-7_16_3",
            "curl-7_16_2",
            "curl-7_16_1",
            "curl-7_16_0",
            "curl-7_15_6-prepipeline",
            "curl-7_15_5",
            "curl-7_15_4",
            "curl-7_15_3",
            "curl-7_15_2",
            "curl-7_15_1",
            "curl-7_15_0",
            "curl-7_14_1",
            "curl-7_14_0",
            "curl-7_13_2",
            "curl-7_13_1",
            "before_ftp_statemachine",
            "curl-7_13_0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-27535.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:35.412611347Z",
      "provider": "osv",
      "references": [
        "https://cert-portal.siemens.com/productcert/html/ssa-398330.html",
        "https://cert-portal.siemens.com/productcert/html/ssa-806742.html",
        "https://cert-portal.siemens.com/productcert/html/ssa-943925.html",
        "https://hackerone.com/reports/1892780",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/27xxx/CVE-2023-27535.json",
        "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/36NBD5YLJXXEDZLDGNFCERWRYJQ6LAQW/",
        "https://nvd.nist.gov/vuln/detail/CVE-2023-27535",
        "https://security.gentoo.org/glsa/202310-12",
        "https://security.netapp.com/advisory/ntap-20230420-0010/",
        "https://lists.debian.org/debian-lts-announce/2023/04/msg00025.html"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-305"
        ],
        "cna_assigner": "hackerone",
        "unresolved_ranges": [
          {
            "extracted_events": [
              {
                "range": [
                  {
                    "fixed": "8.0.0"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "VersionTextExtraction"
              }
            ]
          }
        ],
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/27xxx/CVE-2023-27535.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2023-27535",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 502945,
  "published_at": "2023-03-30T00:00:00+00:00"
}