CVE-2026-47077
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.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected packages
Versions sourced from the GitHub Security Advisory.
| Package | Affected versions | Patched versions |
|---|---|---|
hackneyHex | >= 2.0.0, < 4.0.1 | 4.0.1 |
Affected products
3Patches
Vulnerability mechanics
References
7- cna.erlef.org/cves/CVE-2026-47077.htmlnvdPatchThird Party AdvisoryWEB
- github.com/benoitc/hackney/commit/3d25f9fea26c90609de9d64366fedfe5065413bcnvdPatchWEB
- osv.dev/vulnerability/EEF-CVE-2026-47077nvdPatchThird Party AdvisoryWEB
- github.com/benoitc/hackney/security/advisories/GHSA-jq4m-q6p2-8gwcnvdExploitPatchVendor AdvisoryWEB
- github.com/advisories/GHSA-jq4m-q6p2-8gwcghsaADVISORY
- nvd.nist.gov/vuln/detail/CVE-2026-47077ghsaADVISORY
- github.com/ex-aws/ex_aws_sns/security/advisories/GHSA-8jgf-23q5-x7xxghsaWEB
News mentions
1- Hackney HTTP Client: Ten CVEs Disclosed in a Single Batch — CRLF Injection, Resource Exhaustion, and MoreVypr Intelligence · May 25, 2026