Vulnerability-Lookup

CVE-2026-43970 (GCVE-0-2026-43970)

Vulnerability from cvelistv5 – Published: 2026-05-13 18:43 – Updated: 2026-05-15 04:33

Title

Decompression Bomb in cow_spdy:inflate/2 Allows Memory Exhaustion via Crafted SPDY Frame

Summary

Improper Handling of Highly Compressed Data (Data Amplification) vulnerability in ninenines cowlib allows unauthenticated remote denial of service via memory exhaustion. cow_spdy:inflate/2 in cowlib passes peer-supplied compressed bytes directly to zlib:inflate/2 with no output size bound. The SPDY header compression dictionary (?ZDICT) is public, and zlib compresses long runs of repeated bytes at roughly 1024:1, so a few kilobytes of SPDY frame payload can decompress to gigabytes on the BEAM heap, OOM-killing the node. A single unauthenticated SPDY frame is sufficient to trigger the condition. The parsers for syn_stream, syn_reply, and headers frame types are all affected via cow_spdy:parse_headers/2. This issue affects cowlib from 0.1.0 before 2.16.1.

Severity

8.2 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-05-14 12:38 UTC

CWE

CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification)

Assigner

EEF CNA under the mitre root

CNA scorecard A 97/100 over 345 records in the last 180 days details

References

3 references

URL	Tags
https://cna.erlef.org/cves/CVE-2026-43970.html	relatedthird-party-advisory
https://osv.dev/vulnerability/EEF-CVE-2026-43970	related
https://github.com/ninenines/cowlib/commit/16aad3…	patch

Impacted products

2 products

Vendor	Product	Version	CPE status
ninenines	cowlib	Affected: 0.1.0 , < 2.16.1 (semver) cpe:2.3:a:ninenines:cowlib::::::::
ninenines	cowlib	Affected: fad5c0049df278cc498b6cdb519b09e845a070a8 , < 16aad3fb9f81f5cda4d1706ff0c54237c619c282 (git) cpe:2.3:a:ninenines:cowlib::::::::

Credits

Peter Ullrich Loïc Hoguin

Show details on NVD website

JSON

To clipboard

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              "shortName": "CISA-ADP"
            },
            "title": "CISA ADP Vulnrichment"
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        ],
        "cna": {
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              "cpes": [
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              ],
              "repo": "https://github.com/ninenines/cowlib",
              "vendor": "ninenines",
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              ],
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              "versions": [
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          "credits": [
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            },
            {
              "tags": [
                "related"
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              "url": "https://osv.dev/vulnerability/EEF-CVE-2026-43970"
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              "url": "https://github.com/ninenines/cowlib/commit/16aad3fb9f81f5cda4d1706ff0c54237c619c282"
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                  "value": "\u003cp\u003eUpgrade to cowlib 2.16.1 or later, in which the \u003ctt\u003ecow_spdy\u003c/tt\u003e module has been removed entirely. No patched version of \u003ctt\u003ecow_spdy\u003c/tt\u003e will be provided. Migrate away from SPDY, which has been deprecated since 2015 in favour of HTTP/2.\u003c/p\u003e"
                }
              ],
              "value": "Upgrade to cowlib 2.16.1 or later, in which the cow_spdy module has been removed entirely. No patched version of cow_spdy will be provided. Migrate away from SPDY, which has been deprecated since 2015 in favour of HTTP/2."
            }
          ],
          "source": {
            "discovery": "EXTERNAL"
          },
          "title": "Decompression Bomb in cow_spdy:inflate/2 Allows Memory Exhaustion via Crafted SPDY Frame",
          "x_generator": {
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        "datePublished": "2026-05-13T18:43:11.640Z",
        "dateReserved": "2026-05-04T18:23:25.574Z",
        "dateUpdated": "2026-05-15T04:33:30.898Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}

FKIE_CVE-2026-43970

Vulnerability from fkie_nvd - Published: 2026-05-13 19:17 - Updated: 2026-10-26 17:10

Severity

8.2 (High) - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Summary

References

	URL	Tags
	6b3ad84c-e1a6-4bf7-a703-f496b71e49db	https://cna.erlef.org/cves/CVE-2026-43970.html
	6b3ad84c-e1a6-4bf7-a703-f496b71e49db	https://github.com/ninenines/cowlib/commit/16aad3fb9f81f5cda4d1706ff0c54237c619c282
	6b3ad84c-e1a6-4bf7-a703-f496b71e49db	https://osv.dev/vulnerability/EEF-CVE-2026-43970

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "collectionURL": "https://repo.hex.pm",
          "cpes": [
            "cpe:2.3:a:ninenines:cowlib:*:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unaffected",
          "modules": [
            "cow_spdy"
          ],
          "packageName": "cowlib",
          "packageURL": "pkg:hex/cowlib",
          "product": "cowlib",
          "programFiles": [
            "src/cow_spdy.erl"
          ],
          "programRoutines": [
            {
              "name": "cow_spdy:parse/2"
            },
            {
              "name": "cow_spdy:inflate/2"
            },
            {
              "name": "cow_spdy:parse_headers/2"
            },
            {
              "name": "cow_spdy:parse_headers/4"
            }
          ],
          "repo": "https://github.com/ninenines/cowlib",
          "vendor": "ninenines",
          "versions": [
            {
              "lessThan": "2.16.1",
              "status": "affected",
              "version": "0.1.0",
              "versionType": "semver"
            }
          ]
        },
        {
          "collectionURL": "https://github.com",
          "cpes": [
            "cpe:2.3:a:ninenines:cowlib:*:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unaffected",
          "modules": [
            "cow_spdy"
          ],
          "packageName": "ninenines/cowlib",
          "packageURL": "pkg:github/ninenines/cowlib",
          "product": "cowlib",
          "programFiles": [
            "src/cow_spdy.erl"
          ],
          "programRoutines": [
            {
              "name": "cow_spdy:parse/2"
            },
            {
              "name": "cow_spdy:inflate/2"
            },
            {
              "name": "cow_spdy:parse_headers/2"
            },
            {
              "name": "cow_spdy:parse_headers/4"
            }
          ],
          "repo": "https://github.com/ninenines/cowlib",
          "vendor": "ninenines",
          "versions": [
            {
              "lessThan": "16aad3fb9f81f5cda4d1706ff0c54237c619c282",
              "status": "affected",
              "version": "fad5c0049df278cc498b6cdb519b09e845a070a8",
              "versionType": "git"
            }
          ]
        }
      ],
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Improper Handling of Highly Compressed Data (Data Amplification) vulnerability in ninenines cowlib allows unauthenticated remote denial of service via memory exhaustion.\n\ncow_spdy:inflate/2 in cowlib passes peer-supplied compressed bytes directly to zlib:inflate/2 with no output size bound. The SPDY header compression dictionary (?ZDICT) is public, and zlib compresses long runs of repeated bytes at roughly 1024:1, so a few kilobytes of SPDY frame payload can decompress to gigabytes on the BEAM heap, OOM-killing the node. A single unauthenticated SPDY frame is sufficient to trigger the condition. The parsers for syn_stream, syn_reply, and headers frame types are all affected via cow_spdy:parse_headers/2.\n\nThis issue affects cowlib from 0.1.0 before 2.16.1."
    },
    {
      "lang": "es",
      "value": "La vulnerabilidad de Manejo Inadecuado de Datos Altamente Comprimidos (Amplificaci\u00f3n de Datos) en ninenines cowlib permite una denegaci\u00f3n de servicio remota no autenticada a trav\u00e9s del agotamiento de la memoria.\n\ncow_spdy:inflate/2 en cowlib pasa los bytes comprimidos suministrados por el par directamente a zlib:inflate/2 sin un l\u00edmite de tama\u00f1o de salida. El diccionario de compresi\u00f3n de cabeceras SPDY (?ZDICT) es p\u00fablico, y zlib comprime largas secuencias de bytes repetidos a una proporci\u00f3n aproximada de 1024:1, por lo que unos pocos kilobytes de carga \u00fatil de trama SPDY pueden descomprimirse a gigabytes en el heap de BEAM, provocando la terminaci\u00f3n del nodo por falta de memoria. Una \u00fanica trama SPDY no autenticada es suficiente para activar la condici\u00f3n. Los analizadores para los tipos de trama syn_stream, syn_reply y headers est\u00e1n todos afectados a trav\u00e9s de cow_spdy:parse_headers/2.\n\nEste problema afecta a cowlib desde la versi\u00f3n 0.1.0 anterior a la 2.16.1."
    }
  ],
  "id": "CVE-2026-43970",
  "lastModified": "2026-10-26T17:10:03.270",
  "metrics": {
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "PRESENT",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 8.2,
          "baseSeverity": "HIGH",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "NONE",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "version": "4.0",
          "vulnAvailabilityImpact": "HIGH",
          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "NONE",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-43970",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-05-14T12:38:59.086048Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-05-13T19:17:25.440",
  "references": [
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://cna.erlef.org/cves/CVE-2026-43970.html"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://github.com/ninenines/cowlib/commit/16aad3fb9f81f5cda4d1706ff0c54237c619c282"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://osv.dev/vulnerability/EEF-CVE-2026-43970"
    }
  ],
  "sourceIdentifier": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-409"
        }
      ],
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "type": "Secondary"
    }
  ]
}

GHSA-84F2-RP86-235P

Vulnerability from github – Published: 2026-05-13 21:32 – Updated: 2026-05-19 20:12

Summary

cowlib: Decompression Bomb in cow_spdy:inflate/2 Allows Memory Exhaustion via Crafted SPDY Frame

Details

Improper Handling of Highly Compressed Data (Data Amplification) vulnerability in ninenines cowlib allows unauthenticated remote denial of service via memory exhaustion.

cow_spdy:inflate/2 in cowlib passes peer-supplied compressed bytes directly to zlib:inflate/2 with no output size bound. The SPDY header compression dictionary (?ZDICT) is public, and zlib compresses long runs of repeated bytes at roughly 1024:1, so a few kilobytes of SPDY frame payload can decompress to gigabytes on the BEAM heap, OOM-killing the node. A single unauthenticated SPDY frame is sufficient to trigger the condition. The parsers for syn_stream, syn_reply, and headers frame types are all affected via cow_spdy:parse_headers/2.

This issue affects cowlib from 0.1.0 before 2.16.1.

Severity

8.2 (High)


                  
                    CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Hex",
        "name": "cowlib"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.1.0"
            },
            {
              "fixed": "2.16.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-43970"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-409"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-19T20:12:01Z",
    "nvd_published_at": "2026-05-13T19:17:25Z",
    "severity": "HIGH"
  },
  "details": "Improper Handling of Highly Compressed Data (Data Amplification) vulnerability in ninenines cowlib allows unauthenticated remote denial of service via memory exhaustion.\n\ncow_spdy:inflate/2 in cowlib passes peer-supplied compressed bytes directly to zlib:inflate/2 with no output size bound. The SPDY header compression dictionary (?ZDICT) is public, and zlib compresses long runs of repeated bytes at roughly 1024:1, so a few kilobytes of SPDY frame payload can decompress to gigabytes on the BEAM heap, OOM-killing the node. A single unauthenticated SPDY frame is sufficient to trigger the condition. The parsers for syn_stream, syn_reply, and headers frame types are all affected via cow_spdy:parse_headers/2.\n\nThis issue affects cowlib from 0.1.0 before 2.16.1.",
  "id": "GHSA-84f2-rp86-235p",
  "modified": "2026-05-19T20:12:01Z",
  "published": "2026-05-13T21:32:06Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43970"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ninenines/cowlib/commit/16aad3fb9f81f5cda4d1706ff0c54237c619c282"
    },
    {
      "type": "WEB",
      "url": "https://cna.erlef.org/cves/CVE-2026-43970.html"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/ninenines/cowlib"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/EEF-CVE-2026-43970"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "cowlib: Decompression Bomb in cow_spdy:inflate/2 Allows Memory Exhaustion via Crafted SPDY Frame"
}

MSRC_CVE-2026-43970

Vulnerability from csaf_microsoft - Published: 2026-05-02 00:00 - Updated: 2026-05-21 01:03

Summary

Decompression Bomb in cow_spdy:inflate/2 Allows Memory Exhaustion via Crafted SPDY Frame

Scope

1 vulnerability in this advisory, including CVE-2026-43970.

CVE-2026-43970

Known affected: 1 product

Open the full advisory

UBUNTU-CVE-2026-43970 (CVE-2026-43970)

Vulnerability from osv_ubuntu – Published: 2026-05-13 19:17 – Updated: 2026-10-17 09:42 – Source website

Details

Severity

8.2 (High)


                    
                      CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-43970	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-43970	REPORT
	https://cna.erlef.org/cves/CVE-2026-43970.html	REPORT
	https://osv.dev/vulnerability/EEF-CVE-2026-43970	REPORT
	https://github.com/ninenines/cowlib/commit/16aad3…	REPORT
	https://github.com/ninenines/cowlib/commit/16aad3…	REPORT

JSON

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{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "erlang-cowlib",
            "binary_version": "1.3.0-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:16.04:LTS",
        "name": "erlang-cowlib",
        "purl": "pkg:deb/ubuntu/erlang-cowlib@1.3.0-1?arch=source\u0026distro=xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.3.0-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "erlang-cowlib",
            "binary_version": "1.3.0-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "erlang-cowlib",
        "purl": "pkg:deb/ubuntu/erlang-cowlib@1.3.0-2?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.3.0-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "erlang-cowlib",
            "binary_version": "1.3.0-3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "erlang-cowlib",
        "purl": "pkg:deb/ubuntu/erlang-cowlib@1.3.0-3?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.3.0-3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "erlang-cowlib",
            "binary_version": "1.3.0-3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "erlang-cowlib",
        "purl": "pkg:deb/ubuntu/erlang-cowlib@1.3.0-3?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.3.0-3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "erlang-cowlib",
            "binary_version": "1.3.0-3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "erlang-cowlib",
        "purl": "pkg:deb/ubuntu/erlang-cowlib@1.3.0-3?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.3.0-3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "erlang-cowlib",
            "binary_version": "1.3.0-3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "erlang-cowlib",
        "purl": "pkg:deb/ubuntu/erlang-cowlib@1.3.0-3?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.3.0-3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "erlang-cowlib",
            "binary_version": "2.19.0-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.10",
        "name": "erlang-cowlib",
        "purl": "pkg:deb/ubuntu/erlang-cowlib@2.19.0-1?arch=source\u0026distro=stonking"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.3.0-3build1",
        "2.19.0-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "erlang-cowlib",
            "binary_version": "1.3.0-3build1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "erlang-cowlib",
        "purl": "pkg:deb/ubuntu/erlang-cowlib@1.3.0-3build1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.3.0-3",
        "1.3.0-3build1"
      ]
    }
  ],
  "aliases": [],
  "details": "Improper Handling of Highly Compressed Data (Data Amplification) vulnerability in ninenines cowlib allows unauthenticated remote denial of service via memory exhaustion. cow_spdy:inflate/2 in cowlib passes peer-supplied compressed bytes directly to zlib:inflate/2 with no output size bound. The SPDY header compression dictionary (?ZDICT) is public, and zlib compresses long runs of repeated bytes at roughly 1024:1, so a few kilobytes of SPDY frame payload can decompress to gigabytes on the BEAM heap, OOM-killing the node. A single unauthenticated SPDY frame is sufficient to trigger the condition. The parsers for syn_stream, syn_reply, and headers frame types are all affected via cow_spdy:parse_headers/2. This issue affects cowlib from 0.1.0 before 2.16.1.",
  "id": "UBUNTU-CVE-2026-43970",
  "modified": "2026-10-17T09:42:29Z",
  "published": "2026-05-13T19:17:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-43970"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-43970"
    },
    {
      "type": "REPORT",
      "url": "https://cna.erlef.org/cves/CVE-2026-43970.html"
    },
    {
      "type": "REPORT",
      "url": "https://osv.dev/vulnerability/EEF-CVE-2026-43970"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/ninenines/cowlib/commit/16aad3fb9f81f5cda4d1706ff0c54237c619c282"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/ninenines/cowlib/commit/16aad3fb9f81f5cda4d1706ff0c54237c619c282"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-43970"
  ]
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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UBUNTU-CVE-2026-43970 (CVE-2026-43970)

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