rust-openssl: Unchecked callback-returned length in PSK and cookie generate trampolines can cause OpenSSL to leak adjacent memory to the network peer

{
  "id": "6d888a223d70f85d084f9a87d131269d812dd478ec769d9da486ef72df30659c",
  "url": "https://osv.dev/vulnerability/CVE-2026-41898",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "rust-openssl: Unchecked callback-returned length in PSK and cookie generate trampolines can cause OpenSSL to leak adjacent memory to the network peer",
    "summary": "rust-openssl provides OpenSSL bindings for the Rust programming language. From 0.9.24 to before 0.10.78, the FFI trampolines behind SslContextBuilder::set_psk_client_callback, set_psk_server_callback, set_cookie_generate_cb, and set_stateless_cookie_generate_cb forwarded the user closure's returned usize directly to OpenSSL without checking it against the &mut [u8] that was handed to the closure. This can lead to buffer overflows and other unintended consequences. This vulnerability is fixed in 0.10.78.",
    "evidence": "osv:CVE-2026-41898",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-41898",
      "aliases": [
        "CVE-2026-41898",
        "GHSA-hppc-g8h3-xhp3"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/rust-openssl/rust-openssl",
              "type": "GIT",
              "events": [
                {
                  "introduced": "95c7bf3cbadf7cbb37dd27ea706740f01559c435"
                },
                {
                  "fixed": "a6debf535674c9a073f455158743e6ba094cf1b4"
                },
                {
                  "fixed": "1d109020d98fff2fb2e45c39a373af3dff99b24c"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:rust-openssl_project:rust-openssl:*:*:*:*:*:rust:*:*",
                    "range": [
                      {
                        "introduced": "0.9.24"
                      },
                      {
                        "fixed": "0.10.78"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "1d109020d98fff2fb2e45c39a373af3dff99b24c"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "a6debf535674c9a073f455158743e6ba094cf1b4"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "openssl-v0.10.78"
                  }
                ]
              }
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-41898.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:50.387701171Z",
      "provider": "osv",
      "references": [
        "https://github.com/rust-openssl/rust-openssl/releases/tag/openssl-v0.10.78",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/41xxx/CVE-2026-41898.json",
        "https://github.com/rust-openssl/rust-openssl/security/advisories/GHSA-hppc-g8h3-xhp3",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-41898",
        "https://github.com/rust-openssl/rust-openssl/commit/1d109020d98fff2fb2e45c39a373af3dff99b24c",
        "https://github.com/rust-openssl/rust-openssl/pull/2607"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-126",
          "CWE-130"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/41xxx/CVE-2026-41898.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-41898",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 518773,
  "published_at": "2026-04-24T17:20:38.073+00:00"
}