Vulnerability details
CVE-2026-47071
SOCKS5 TLS upgrade ignores caller timeout in hackney
Official 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.
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 8.2High | 4.0 | CVEProject cvelistV5 (CNA) (EEF) | 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 |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| benoitc | hackney | 0.10.0 ≤ v < 4.0.1 | CVEProject cvelistV5 (CNA) |
| benoitc | hackney | 34cdbd1d20a282aacc286a89327465a3925b4c5d ≤ v < 5ccdab725c561a6f03d05a51f2d0664f98236dae | CVEProject cvelistV5 (CNA) |
References and advisories
4Details
- Published
- 2026-05-25
- Last updated
- 2026-05-27
- State
- Published
- Assigner (CNA)
- EEF
Exploit prediction (EPSS)
SSVC assessment (CISA)
- Automatable
- Yes
- Exploitation
- Proof of concept
- Technical impact
- Partial
Weaknesses (CWE)
- CWE-400Uncontrolled Resource Consumption