{"id":"CVE-2026-47067","state":"PUBLISHED","title":"Atom table exhaustion via unrecognized URL schemes in hackney","description":"Allocation of Resources Without Limits or Throttling vulnerability in benoitc hackney allows Flooding. The URL parser in src/hackney_url.erl converts every unrecognized URL scheme to a permanent BEAM atom via binary_to_atom/2. BEAM atoms are never garbage-collected and the atom table defaults to a hard limit of 1,048,576 entries. An attacker who can supply URLs with attacker-chosen scheme prefixes — directly as request targets, as configured webhook URLs, or via Location headers followed during redirects — can exhaust the atom table and crash the entire BEAM VM with system_limit.\n\nThis issue affects hackney: from 2.0.0 before 4.0.1.","publishedAt":"2026-05-25T14:00:48.507Z","updatedAt":"2026-05-27T15:41:27.821Z","severity":{"score":8.7,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","source":"EEF"},"assigner":"EEF","products":["benoitc hackney"],"affected":[{"vendor":"benoitc","product":"hackney","packageName":"hackney","packageURL":"pkg:hex/hackney","defaultStatus":"unaffected","versions":[{"version":"2.0.0","status":"affected","lessThan":"4.0.1","versionType":"semver"}],"collectionURL":"https://repo.hex.pm","cpes":["cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*"],"modules":["hackney_url"],"programFiles":["src/hackney_url.erl"],"programRoutines":[{"name":"hackney_url:parse_url/1"}],"repo":"https://github.com/benoitc/hackney"},{"vendor":"benoitc","product":"hackney","packageName":"benoitc/hackney","packageURL":"pkg:github/benoitc/hackney","defaultStatus":"unaffected","versions":[{"version":"d9713695c0d99855d12c73fd8a0b4be0543950c4","status":"affected","lessThan":"31f6f0e27e096ad88743dfded4f030a3ee74972e","versionType":"git"}],"collectionURL":"https://github.com","cpes":["cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*"],"modules":["hackney_url"],"programFiles":["src/hackney_url.erl"],"programRoutines":[{"name":"hackney_url:parse_url/1"}],"repo":"https://github.com/benoitc/hackney"}],"references":["https://github.com/benoitc/hackney/security/advisories/GHSA-9653-rcfr-5c62","https://cna.erlef.org/cves/CVE-2026-47067.html","https://osv.dev/vulnerability/EEF-CVE-2026-47067","https://github.com/benoitc/hackney/commit/31f6f0e27e096ad88743dfded4f030a3ee74972e"],"weaknesses":["CWE-770"],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/47xxx/CVE-2026-47067.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-47067","state":"PUBLISHED","datePublished":"2026-05-25T14:00:48.507Z","dateUpdated":"2026-05-27T15:41:27.821Z","assignerShortName":"EEF","assignerOrgId":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db","dateReserved":"2026-05-18T17:28:08.321Z"},"containers":{"cna":{"title":"Atom table exhaustion via unrecognized URL schemes in hackney","descriptions":[{"lang":"en","value":"Allocation of Resources Without Limits or Throttling vulnerability in benoitc hackney allows Flooding. The URL parser in src/hackney_url.erl converts every unrecognized URL scheme to a permanent BEAM atom via binary_to_atom/2. BEAM atoms are never garbage-collected and the atom table defaults to a hard limit of 1,048,576 entries. An attacker who can supply URLs with attacker-chosen scheme prefixes — directly as request targets, as configured webhook URLs, or via Location headers followed during redirects — can exhaust the atom table and crash the entire BEAM VM with system_limit.\n\nThis issue affects hackney: from 2.0.0 before 4.0.1."}],"affected":[{"vendor":"benoitc","product":"hackney","packageName":"hackney","packageURL":"pkg:hex/hackney","defaultStatus":"unaffected","versions":[{"version":"2.0.0","status":"affected","lessThan":"4.0.1","versionType":"semver"}],"collectionURL":"https://repo.hex.pm","cpes":["cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*"],"modules":["hackney_url"],"programFiles":["src/hackney_url.erl"],"programRoutines":[{"name":"hackney_url:parse_url/1"}],"repo":"https://github.com/benoitc/hackney"},{"vendor":"benoitc","product":"hackney","packageName":"benoitc/hackney","packageURL":"pkg:github/benoitc/hackney","defaultStatus":"unaffected","versions":[{"version":"d9713695c0d99855d12c73fd8a0b4be0543950c4","status":"affected","lessThan":"31f6f0e27e096ad88743dfded4f030a3ee74972e","versionType":"git"}],"collectionURL":"https://github.com","cpes":["cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*"],"modules":["hackney_url"],"programFiles":["src/hackney_url.erl"],"programRoutines":[{"name":"hackney_url:parse_url/1"}],"repo":"https://github.com/benoitc/hackney"}],"references":[{"url":"https://github.com/benoitc/hackney/security/advisories/GHSA-9653-rcfr-5c62","tags":["vendor-advisory","related"]},{"url":"https://cna.erlef.org/cves/CVE-2026-47067.html","tags":["related"]},{"url":"https://osv.dev/vulnerability/EEF-CVE-2026-47067","tags":["related"]},{"url":"https://github.com/benoitc/hackney/commit/31f6f0e27e096ad88743dfded4f030a3ee74972e","tags":["patch"]}],"metrics":[{"cvssV4_0":{"attackComplexity":"LOW","attackRequirements":"NONE","attackVector":"NETWORK","baseScore":8.7,"baseSeverity":"HIGH","privilegesRequired":"NONE","subAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"NONE","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","version":"4.0","vulnAvailabilityImpact":"HIGH","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-770","description":"CWE-770 Allocation of Resources Without Limits or Throttling","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"EEF","orgId":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db","dateUpdated":"2026-05-27T15:41:27.821Z"},"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*","versionEndExcluding":"4.0.1","versionStartIncluding":"2.0.0","vulnerable":true}],"negate":false,"operator":"AND"}],"operator":"AND"}],"credits":[{"lang":"en","type":"finder","value":"Peter Ullrich"},{"lang":"en","type":"remediation developer","value":"Benoit Chesneau"},{"lang":"en","type":"analyst","value":"Jonatan Männchen / EEF"}],"impacts":[{"capecId":"CAPEC-125","descriptions":[{"lang":"en","value":"CAPEC-125 Flooding"}]}],"source":{"discovery":"EXTERNAL"},"x_generator":{"engine":"cvelib 1.8.0"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/benoitc/hackney/security/advisories/GHSA-9653-rcfr-5c62","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-05-26T15:45:32.232194Z","id":"CVE-2026-47067","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-05-26T15:45:36.464Z"}}]}}}