Weakness Type (CWE)

CWE-400 — CWE-400 Uncontrolled Resource Consumption

CAPEC

CVSS 4.0 Score

8.2

HIGH

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Vulnerability description

Uncontrolled Resource Consumption vulnerability in benoitc hackney allows Flooding.

The SOCKS5 transport in src/hackney_socks5.erl correctly applies the caller-supplied timeout to the SOCKS5 negotiation phase, but then upgrades the connection to TLS using the two-argument form ssl:connect/2, which defaults to an infinite timeout. The Timeout value is in scope at the call site but is not forwarded. A hostile SOCKS5 proxy that completes the SOCKS5 handshake normally and then goes silent (or sends a partial TLS ServerHello and stalls) will cause the connecting process to block indefinitely, regardless of the connect_timeout or recv_timeout options supplied by the caller.

This issue affects hackney: from 0.10.0 before 4.0.1.

Affected

pkg:hex/hackney

Module Source File Routine
hackney_socks5 src/hackney_socks5.erl hackney_socks5:connect/4
Status Type Version Changes / Fixed in
affected semver ⓘ 0.10.0 < 4.0.1

pkg:github/benoitc/hackney

Module Source File Routine
hackney_socks5 src/hackney_socks5.erl hackney_socks5:connect/4
Status Type Version Changes / Fixed in
affected git ⓘ 34cdbd1d20 < 5ccdab725c

References

Credits

  • Finder: Peter Ullrich
  • Remediation developer: Benoit Chesneau
  • Analyst: Jonatan Männchen

CVE record as JSON:  GET /cves/CVE-2026-47071.json
OSV record as JSON:  GET /osv/EEF-CVE-2026-47071.json