CVE-2026-47071

HIGH

SOCKS5 TLS upgrade ignores caller timeout in hackney

Title source: cna
STIX 2.1

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.

Scores

CVSS v3 7.5
EPSS 0.0067
EPSS Percentile 47.0%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation poc
Automatable yes
Technical Impact partial

Details

CWE
CWE-400
Status published
Products (2)
benoitc/hackney 0.10.0 - 4.0.1 (2 CPE variants)
benoitc/hackney 34cdbd1d20a282aacc286a89327465a3925b4c5d - 5ccdab725c561a6f03d05a51f2d0664f98236dae
Published May 25, 2026
Tracked Since May 25, 2026