SOCKS5 TLS upgrade ignores caller timeout in hackney_CVE-2026-47071

8.2 / 10

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

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.

Basic Information

ID CVE-2026-47071

Source EEF

Published May 25, 2026 at 14:00

Affected Product

Vendor benoitc

Product hackney

Version 0.10.0

Affected Versions benoitc hackney 0.10.0
benoitc hackney 34cdbd1d20a282aacc286a89327465a3925b4c5d

CWE Classification

CWE-400

References

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    "published": "2026-05-25T14:00:41.112Z",
    "modified": "2026-05-25T14:00:41.112Z",
    "type": "cve",
    "title": "SOCKS5 TLS upgrade ignores caller timeout in hackney",
    "source": "EEF",
    "references": "https://github.com/benoitc/hackney/security/advisories/GHSA-gp9c-pm5m-5cxr\nhttps://cna.erlef.org/cves/CVE-2026-47071.html\nhttps://osv.dev/vulnerability/EEF-CVE-2026-47071\nhttps://github.com/benoitc/hackney/commit/5ccdab725c561a6f03d05a51f2d0664f98236dae",
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