Security advisory

{
  "id": "29235afffb1486891df5db84585fb9a71308c3097634226176e30dc15229774b",
  "url": "https://osv.dev/vulnerability/CVE-2020-1763",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2020-1763",
    "summary": "An out-of-bounds buffer read flaw was found in the pluto daemon of libreswan from versions 3.27 till 3.31 where, an unauthenticated attacker could use this flaw to crash libreswan by sending specially-crafted IKEv1 Informational Exchange packets. The daemon respawns after the crash.",
    "evidence": "osv:CVE-2020-1763",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2020-1763",
      "aliases": [
        "CVE-2020-1763"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/libreswan/libreswan",
              "type": "GIT",
              "events": [
                {
                  "introduced": "9b1394ea1190b38005e89a4d5188ba9d63506d0a"
                },
                {
                  "last_affected": "f54f585809424a075a364c1266e131395685997c"
                },
                {
                  "introduced": "aba60a4fcc11765ecd2fb9352427c722a704bd8a"
                },
                {
                  "last_affected": "aba60a4fcc11765ecd2fb9352427c722a704bd8a"
                },
                {
                  "fixed": "471a3e41a449d7c753bc4edbba4239501bb62ba8"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:libreswan:libreswan:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "3.27"
                      },
                      {
                        "last_affected": "3.31"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:libreswan:libreswan:3.5:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "3.5"
                      },
                      {
                        "last_affected": "3.5"
                      }
                    ],
                    "source": "CPE_STRING"
                  },
                  {
                    "range": [
                      {
                        "fixed": "471a3e41a449d7c753bc4edbba4239501bb62ba8"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "3.5",
            "v3.31",
            "v3.30",
            "v3.28",
            "v3.27",
            "v3.5"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-1763.json",
            "vanir_signatures": [
              {
                "id": "CVE-2020-1763-35f05910",
                "digest": {
                  "threshold": 0.9,
                  "line_hashes": [
                    "192785595241567337803171226975667384092",
                    "151688309535239392845873598075242329199",
                    "267668679704350220890171108057600248734",
                    "320866523120216577581671520102311072700"
                  ]
                },
                "source": "https://github.com/libreswan/libreswan/commit/471a3e41a449d7c753bc4edbba4239501bb62ba8",
                "target": {
                  "file": "programs/pluto/ikev1.c"
                },
                "deprecated": false,
                "signature_type": "Line",
                "signature_version": "v1"
              },
              {
                "id": "CVE-2020-1763-7142646b",
                "digest": {
                  "length": 9557,
                  "function_hash": "249042612403858674025323106804503298179"
                },
                "source": "https://github.com/libreswan/libreswan/commit/471a3e41a449d7c753bc4edbba4239501bb62ba8",
                "target": {
                  "file": "programs/pluto/ikev1.c",
                  "function": "process_packet_tail"
                },
                "deprecated": false,
                "signature_type": "Function",
                "signature_version": "v1"
              }
            ],
            "vanir_signatures_modified": "2026-10-20T13:52:00Z"
          }
        }
      ],
      "modified": "2026-10-20T13:52:00.206325734Z",
      "provider": "osv",
      "references": [
        "https://cert-portal.siemens.com/productcert/pdf/ssa-379803.pdf",
        "https://security.gentoo.org/glsa/202007-21",
        "https://us-cert.cisa.gov/ics/advisories/icsa-21-040-04",
        "https://www.debian.org/security/2020/dsa-4684",
        "https://bugzilla.redhat.com/show_bug.cgi?id=1813329",
        "https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-1763",
        "https://github.com/libreswan/libreswan/commit/471a3e41a449d7c753bc4edbba4239501bb62ba8",
        "https://libreswan.org/security/CVE-2020-1763/CVE-2020-1763.txt"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2020-1763",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 388299,
  "published_at": "2020-05-12T14:15:12.58+00:00"
}