CVE-2026-47071
SOCKS5 TLS upgrade ignores caller timeout in hackney
- Published
- Updated
- Reserved
- Assigned by
- EEF
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
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| EEFCNA (assigner) | 4.0 | High8.2 | 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 |
| NVDNVD · Analyzed | 4.0 | High8.2 | 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 |
- EPSS (exploitation in 30 days)
- 0.75% · top 45% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.2.
Weakness
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- HexhackneyGHSA-gp9c-pm5m-5cxr (opens in a new tab)
References (4)
- https://github.com/benoitc/hackney/security/advisories/GHSA-gp9c-pm5m-5cxr (opens in a new tab)vendor-advisoryrelatedexploit
- https://cna.erlef.org/cves/CVE-2026-47071.html (opens in a new tab)related
- https://osv.dev/vulnerability/EEF-CVE-2026-47071 (opens in a new tab)related
- https://github.com/benoitc/hackney/commit/5ccdab725c561a6f03d05a51f2d0664f98236dae (opens in a new tab)patch
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-gp9c-pm5m-5cxr (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-47071)Record last updated .