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Medium

fs2: Half-shutdown of socket during TLS handshake may result in spin loop on opposite side

Type: advisorySources: OSV

fs2 is a compositional, streaming I/O library for Scala. Versions up to and including 2.5.12, 3.0.0-M1 through 3.12.2, and 3.13.0-M1 through 3.13.0-M6 are vulnerable to denial of service attacks though TLS sessions using fs2-io on the JVM using the fs2.io.net.tls package. When establishing a TLS session, if one side of the connection shuts down `write` while the peer side is awaiting more data to progress the TLS handshake, the peer side will spin loop on the socket read, fully utilizing a CPU. The CPU is consumed until the overall connection is closed, potentially shutting down a fs2-io powered server. This issue is fixed in versions 2.5.13, 3.12.1, and 3.13.0-M7.

Products
Not specified
Affected versions
Not specified
Fixed versions
Not specified
CVEs
CVE-2025-58369
Confirmed fixed CVEs
Not specified
Updated in this feed
7 Nov 2026, 09:10 UTC · Revision 1

Source evidence

fs2: Half-shutdown of socket during TLS handshake may result in spin loop on opposite side

core-osv · Original source

Published 5 Sept 2025, 21:59 UTC

fs2 is a compositional, streaming I/O library for Scala. Versions up to and including 2.5.12, 3.0.0-M1 through 3.12.2, and 3.13.0-M1 through 3.13.0-M6 are vulnerable to denial of service attacks though TLS sessions using fs2-io on the JVM using the fs2.io.net.tls package. When establishing a TLS session, if one side of the connection shuts down `write` while the peer side is awaiting more data to progress the TLS handshake, the peer side will spin loop on the socket read, fully utilizing a CPU. The CPU is consumed until the overall connection is closed, potentially shutting down a fs2-io powered server. This issue is fixed in versions 2.5.13, 3.12.1, and 3.13.0-M7.

osv:CVE-2025-58369
Complete source record
{
  "id": "3b7d6910d6bc07084105be728ba93432fc7d6887adea1ce4a1c0f79a7372a0b5",
  "url": "https://osv.dev/vulnerability/CVE-2025-58369",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "fs2: Half-shutdown of socket during TLS handshake may result in spin loop on opposite side",
    "summary": "fs2 is a compositional, streaming I/O library for Scala. Versions up to and including 2.5.12, 3.0.0-M1 through 3.12.2, and 3.13.0-M1 through 3.13.0-M6 are vulnerable to denial of service attacks though TLS sessions using fs2-io on the JVM using the fs2.io.net.tls package. When establishing a TLS session, if one side of the connection shuts down `write` while the peer side is awaiting more data to progress the TLS handshake, the peer side will spin loop on the socket read, fully utilizing a CPU. The CPU is consumed until the overall connection is closed, potentially shutting down a fs2-io powered server. This issue is fixed in versions 2.5.13, 3.12.1, and 3.13.0-M7.",
    "evidence": "osv:CVE-2025-58369",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2025-58369",
      "aliases": [
        "CVE-2025-58369",
        "GHSA-rrw2-px9j-qffj"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/typelevel/fs2",
              "type": "GIT",
              "events": [
                {
                  "introduced": "69a2778184eb2d9084c20fc1560c074231914d60"
                },
                {
                  "fixed": "46e2dc3abf994dcf3d0b804b2ddb3c10c04d4976"
                },
                {
                  "introduced": "5af859e9cca301df4e44368d2cbd1110d3d176bf"
                },
                {
                  "fixed": "55b55dbe3199abecd79e739048d5c5046cd65b7a"
                },
                {
                  "introduced": "0"
                },
                {
                  "fixed": "edf0c4f2e660360d1c1a8c5377ce32294de89238"
                },
                {
                  "fixed": "5c6c4c6c1ef330f7e6b53661ecc63d5f5ba8885c"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "3.0.0-M1"
                      },
                      {
                        "fixed": "3.12.2"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "introduced": "3.13.0-M1"
                      },
                      {
                        "fixed": "3.13.0-M7"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "2.5.13"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "46e2dc3abf994dcf3d0b804b2ddb3c10c04d4976"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "5c6c4c6c1ef330f7e6b53661ecc63d5f5ba8885c"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "edf0c4f2e660360d1c1a8c5377ce32294de89238"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "46e2dc3abf994dcf3d0b804b2ddb3c10c04d4976"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v3.12.2"
                  },
                  {
                    "range": [
                      {
                        "fixed": "55b55dbe3199abecd79e739048d5c5046cd65b7a"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v3.13.0-M7"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v2.5.12",
            "v3.12.1",
            "v3.12.0",
            "v3.13.0-M6",
            "v3.13.0-M5",
            "v3.13.0-M4",
            "v3.13.0-M3",
            "v3.13.0-M2",
            "v3.13.0-M1",
            "v3.12.0-RC2",
            "v3.11.0",
            "v2.5.11",
            "v3.10.2",
            "v3.10.1",
            "v3.10.0",
            "v3.9.4",
            "v3.9.3",
            "v3.9.2",
            "v3.9.1",
            "v3.9.0",
            "v3.8.0",
            "v3.7.0",
            "v3.7.0-RC5",
            "v3.7.0-RC4",
            "v3.7.0-RC3",
            "v3.7.0-RC2",
            "v3.6.1",
            "v3.6.0",
            "v3.5.0",
            "v3.4.0",
            "v3.3.0",
            "v3.2.14",
            "v3.2.13",
            "v3.2.12",
            "v3.2.9",
            "v3.2.10",
            "v3.2.8",
            "v3.2.7",
            "v3.2.6",
            "v3.2.5",
            "v3.2.4",
            "v3.2.3",
            "v2.5.10",
            "v3.2.2",
            "v3.2.1",
            "v3.2.0",
            "v3.1.6",
            "v3.1.5",
            "v3.1.4",
            "v3.1.2",
            "v3.1.1",
            "v3.1.0",
            "v2.5.9",
            "v2.5.8",
            "v3.0.6",
            "v3.0.5",
            "v2.5.7",
            "v2.5.6",
            "v3.0.4",
            "v3.0.3",
            "v2.5.5",
            "v3.0.2",
            "v2.5.4",
            "v3.0.1",
            "v2.5.3",
            "v3.0.0",
            "v2.5.2",
            "v3.0.0-M9",
            "v2.5.1",
            "v2.5.0-RC1",
            "v3.0.0-M8",
            "v2.5.0",
            "v3.0.0-M7",
            "v2.5.0-M3",
            "v3.0.0-M6",
            "v3.0.0-M5",
            "v3.0.0-M4",
            "v2.5.0-M2",
            "v3.0.0-M3",
            "v2.5.0-M1",
            "v3.0.0-M2",
            "v2.4.4",
            "v3.0.0-M1",
            "v2.4.3",
            "v2.4.2",
            "v2.4.1",
            "v2.4.0",
            "v2.3.0",
            "v2.2.2",
            "v2.2.1",
            "v2.2.0",
            "v2.1.0",
            "v2.0.1",
            "v2.0.0",
            "v1.1.0-M2",
            "v1.1.0-M1",
            "v1.0.4",
            "v1.0.3",
            "v1.0.2",
            "v1.0.1",
            "v1.0.0",
            "v1.0.0-RC2",
            "v1.0.0-RC1",
            "v1.0.0-M5",
            "v1.0.0-M4",
            "v1.0.0-M3",
            "v1.0.0-M2",
            "v1.0.0-M1",
            "v0.10.2",
            "v0.10.1",
            "v0.10.0",
            "v0.10.0-RC2",
            "v0.10.0-RC1",
            "v0.10.0-M11",
            "v0.10.0-M10",
            "v0.10.0-M9",
            "v0.10.0-M8",
            "v0.10.0-M7",
            "v0.10.0-M6",
            "v0.10.0-M5",
            "v0.10.0-M4",
            "v0.10.0-M3",
            "v0.10.0-M2",
            "v0.10.0-M1",
            "v0.9.1",
            "v0.9.0",
            "v0.9.0-RC2",
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            "v0.9.0-M5",
            "v0.9.0-M4",
            "v0.9.0-M3",
            "v0.9.0-M2",
            "v0.9.0-M1",
            "redesign-complex-interpreter",
            "release/0.7",
            "release/0.5"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-58369.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:50.354877351Z",
      "provider": "osv",
      "references": [
        "https://github.com/typelevel/fs2/releases/tag/v3.12.2",
        "https://github.com/typelevel/fs2/releases/tag/v3.13.0-M7",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/58xxx/CVE-2025-58369.json",
        "https://github.com/typelevel/fs2/security/advisories/GHSA-rrw2-px9j-qffj",
        "https://nvd.nist.gov/vuln/detail/CVE-2025-58369",
        "https://github.com/typelevel/fs2/issues/3590",
        "https://github.com/typelevel/fs2/commit/46e2dc3abf994dcf3d0b804b2ddb3c10c04d4976",
        "https://github.com/typelevel/fs2/commit/5c6c4c6c1ef330f7e6b53661ecc63d5f5ba8885c",
        "https://github.com/typelevel/fs2/commit/edf0c4f2e660360d1c1a8c5377ce32294de89238"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-400"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/58xxx/CVE-2025-58369.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2025-58369",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 518842,
  "published_at": "2025-09-05T21:59:58.981+00:00"
}