CVE-2026-47067
Allocation of Resources Without Limits or Throttling vulnerability in benoitc hackney allows Flooding.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.75%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 4.0
- 8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/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/M
- EPSS
- 0.75% probability · 53th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-770
- Affected
- benoitc/hackney
- Source
- 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
References
- https://cna.erlef.org/cves/CVE-2026-47067.htmlPatch, Third Party Advisory
- https://github.com/benoitc/hackney/commit/31f6f0e27e096ad88743dfded4f030a3ee74972ePatch
- https://github.com/benoitc/hackney/security/advisories/GHSA-9653-rcfr-5c62Exploit, Patch, Vendor Advisory
- https://osv.dev/vulnerability/EEF-CVE-2026-47067Patch, Third Party Advisory
- https://github.com/benoitc/hackney/security/advisories/GHSA-9653-rcfr-5c62Exploit, Patch, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.