Vulnerability in benoitc hackney

[ Description ]Official description

Allocation of Resources Without Limits or Throttling vulnerability in hackney_conn in benoitc hackney allows a malicious HTTP server to exhaust client memory via an oversized or highly compressed response body. hackney:request/5 and hackney:body/1 return the whole response body, and nothing bounds how much the connection process buffers. Any server the client requests can trigger it. hackney_conn:read_full_body/2 and the HTTP/2 and HTTP/3 accumulators append every chunk until the body ends. With {auto_decompress, true} the buffered body is then inflated in one step with zlib:gunzip/1 or zlib:inflate/2, which return the whole output at once. This issue affects hackney: from 2.0.0-beta.1 before 4.9.0.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ References ]References

• cna.erlef.org/cves/CVE-2026-97200.html
• github.com/benoitc/hackney/commit/493e8bf83a391548e5101792276ab3fc428fa76c
• github.com/benoitc/hackney/commit/dc41b79339ca0c41e16d3f2dd17172bc2de855d6
• github.com/benoitc/hackney/pull/980
• github.com/benoitc/hackney/releases/tag/4.9.0
• osv.dev/vulnerability/EEF-CVE-2026-97200