Vulnerability Description
Allocation of Resources Without Limits or Throttling vulnerability in benoitc hackney allows Flooding. hackney_h3:await_response_loop/6 accumulates the HTTP/3 response body in memory without any size cap. The after Timeout clause is a per-message inactivity timer that resets on every received chunk, housekeeping message, or settings frame — it is not a wall-clock deadline. A malicious HTTP/3 server that emits one small chunk every Timeout - 1 ms with Fin = false and never sends a final frame keeps the loop alive indefinitely while the accumulation buffer grows linearly without bound, eventually exhausting the BEAM process heap and causing an out-of-memory condition. This issue affects hackney: from 2.0.0 before 4.0.1.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Benoitc | Hackney | >= 2.0.0, < 4.0.1 |
Related Weaknesses (CWE)
References
- https://cna.erlef.org/cves/CVE-2026-47077.htmlPatchThird Party Advisory
- https://github.com/benoitc/hackney/commit/3d25f9fea26c90609de9d64366fedfe5065413Patch
- https://github.com/benoitc/hackney/security/advisories/GHSA-jq4m-q6p2-8gwcExploitPatchVendor Advisory
- https://osv.dev/vulnerability/EEF-CVE-2026-47077PatchThird Party Advisory
- https://github.com/benoitc/hackney/security/advisories/GHSA-jq4m-q6p2-8gwcExploitPatchVendor Advisory
FAQ
What is CVE-2026-47077?
CVE-2026-47077 is a vulnerability with a CVSS score of 7.5 (HIGH). Allocation of Resources Without Limits or Throttling vulnerability in benoitc hackney allows Flooding. hackney_h3:await_response_loop/6 accumulates the HTTP/3 response body in memory without any size ...
How severe is CVE-2026-47077?
CVE-2026-47077 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-47077?
Check the references section above for vendor advisories and patch information. Affected products include: Benoitc Hackney.