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.

This issue affects hackney: from 2.0.0 before 4.0.1.

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History

Tue, 26 May 2026 16:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Mon, 25 May 2026 14:30:00 +0000

Type Values Removed Values Added
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. This issue affects hackney: from 2.0.0 before 4.0.1.
Title Atom table exhaustion via unrecognized URL schemes in hackney
First Time appeared Benoitc
Benoitc hackney
Weaknesses CWE-770
CPEs cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*
Vendors & Products Benoitc
Benoitc hackney
References
Metrics cvssV4_0

{'score': 8.7, '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'}


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cve-icon MITRE

Status: PUBLISHED

Assigner: EEF

Published:

Updated: 2026-05-26T15:45:36.464Z

Reserved: 2026-05-18T17:28:08.321Z

Link: CVE-2026-47067

cve-icon Vulnrichment

Updated: 2026-05-26T15:45:07.470Z

cve-icon NVD

Status : Received

Published: 2026-05-25T15:16:21.740

Modified: 2026-05-25T15:16:21.740

Link: CVE-2026-47067

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-05-26T13:00:48Z

Weaknesses