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 mitre root

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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              "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": [
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              "programRoutines": [
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                {
                  "name": "cow_spdy:parse_headers/4"
                }
              ],
              "repo": "https://github.com/ninenines/cowlib",
              "vendor": "ninenines",
              "versions": [
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                  "status": "affected",
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            }
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              "supportingMedia": [
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              ],
              "value": "The application must use cow_spdy:parse/2 to parse SPDY frames from an untrusted peer. cowboy itself does not use cow_spdy; only direct callers of the cow_spdy API are affected."
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          "cpeApplicability": [
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              "nodes": [
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          "credits": [
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              "type": "finder",
              "value": "Peter Ullrich"
            },
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          ],
          "impacts": [
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          "metrics": [
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                "attackRequirements": "PRESENT",
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                "subConfidentialityImpact": "NONE",
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                "userInteraction": "NONE",
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                "version": "4.0",
                "vulnAvailabilityImpact": "HIGH",
                "vulnConfidentialityImpact": "NONE",
                "vulnIntegrityImpact": "NONE"
              },
              "format": "CVSS",
              "scenarios": [
                {
                  "lang": "en",
                  "value": "GENERAL"
                }
              ]
            }
          ],
          "problemTypes": [
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              "descriptions": [
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                  "cweId": "CWE-409",
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                  "lang": "en",
                  "type": "CWE"
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            }
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          "providerMetadata": {
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            "orgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
            "shortName": "EEF"
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          "references": [
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                "third-party-advisory"
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            },
            {
              "tags": [
                "related"
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              "url": "https://osv.dev/vulnerability/EEF-CVE-2026-43970"
            },
            {
              "tags": [
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              "url": "https://github.com/ninenines/cowlib/commit/16aad3fb9f81f5cda4d1706ff0c54237c619c282"
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              "supportingMedia": [
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                  "base64": false,
                  "type": "text/html",
                  "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": {
            "engine": "cvelib 1.8.0"
          }
        }
      },
      "cveMetadata": {
        "assignerOrgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
        "assignerShortName": "EEF",
        "cveId": "CVE-2026-43970",
        "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: 2026-06-17 10:50

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."
    }
  ],
  "id": "CVE-2026-43970",
  "lastModified": "2026-06-17T10:50:08.667",
  "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: 2026-05-13 19:17 – 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

To clipboard

{
  "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": "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": "2026-05-13T19:17:00Z",
  "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.

Detection rules are retrieved from Rulezet.

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

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

FKIE_CVE-2026-43970

GHSA-84F2-RP86-235P

MSRC_CVE-2026-43970

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

Tags

Sightings

Nomenclature

Related by attack behaviour