CVE-2026-47067
Allocation of Resources Without Throttling in hackney
Publication date: 2026-05-25
Last updated on: 2026-05-25
Assigner: EEF
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| benoitc | hackney | From 2.0.0 (inc) to 4.0.1 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-770 | The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability exists in the benoitc hackney library, specifically in its URL parser located in src/hackney_url.erl. The parser converts every unrecognized URL scheme into a permanent BEAM atom using the binary_to_atom/2 function. Since BEAM atoms are never garbage-collected and the atom table has a fixed limit of 1,048,576 entries, an attacker can supply URLs with attacker-chosen scheme prefixes to exhaust this atom table.
When the atom table is exhausted, it causes the entire BEAM virtual machine (VM) to crash with a system_limit error. This can happen through direct request targets, configured webhook URLs, or Location headers followed during redirects.
How can this vulnerability impact me? :
The primary impact of this vulnerability is a denial of service (DoS) condition. By exhausting the atom table, an attacker can crash the entire BEAM VM running the hackney library, causing the application or service relying on it to become unavailable.
This can disrupt normal operations, potentially leading to downtime, loss of service, and degraded user experience.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
The provided information does not specify how this vulnerability impacts compliance with common standards and regulations such as GDPR or HIPAA.