Resource exhaustion in Benoitc Hackney

CVE-2026-47071

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.

Vulnerability class: DoS (Denial of Service)

EPSS: 0.008 (52.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

  • Benoitc Hackney — versions 0.10.0, 34cdbd1d20a282aacc286a89327465a3925b4c5d

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-47071?
CVE-2026-47071 is a high-severity vulnerability in Benoitc Hackney, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2026-05-25.
How severe is CVE-2026-47071?
High severity. CVSS v3 base score is 7.5 out of 10.