Review reviewHigh

CVE-2026-47071

benoitc hackney

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, re...

CVSS: 8.2
EPSS: 0.75%
CISA KEV: Not listed
Published: 2026.05.26

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability0.75%

Technical severityCVSS 8.2

Vulnerability overview

Affected product and versions

Product: benoitc hackney
Affected versions: >= 0.10.0 < 4.0.1, >= 34cdbd1d20a282aacc286a89327465a3925b4c5d < 5ccdab725c561a6f03d05a51f2d0664f98236dae
Fixed versions: 4.0.1

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that benoitc hackney and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: 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/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
CWE: CWE-400