8.2
HIGH CVSS 4.0
CVE-2026-47071
SOCKS5 TLS upgrade ignores caller timeout in hackney
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.

INFO

Published Date :

May 25, 2026, 2 p.m.

Last Modified :

May 25, 2026, 2 p.m.

Remotely Exploit :

Yes !

Source :

EEF
Affected Products

The following products are affected by CVE-2026-47071 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 HIGH 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
Solution
Upgrade hackney to a version that fixes infinite timeout in TLS connection.
  • Update hackney to version 4.0.1 or later.
  • Ensure TLS connections respect configured timeouts.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-47071 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-47071 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by 6b3ad84c-e1a6-4bf7-a703-f496b71e49db

    May. 25, 2026

    Action Type Old Value New Value
    Added 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.
    Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-400
    Added Reference https://cna.erlef.org/cves/CVE-2026-47071.html
    Added Reference https://github.com/benoitc/hackney/commit/5ccdab725c561a6f03d05a51f2d0664f98236dae
    Added Reference https://github.com/benoitc/hackney/security/advisories/GHSA-gp9c-pm5m-5cxr
    Added Reference https://osv.dev/vulnerability/EEF-CVE-2026-47071
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.