TI-2026-34672 Aliases CVE-2026-47070 GHSA-h73q-4w9q-82h4

HTTP/3 redirect handler leaks Authorization and Cookie headers to cross-origin redirect target in hackney

MEDIUM 60CWE-601Published 2026-05-25 · Updated 2026-05-27

Key facts

Attack vector: Network
Privileges required: None
User interaction: Passive
Attack complexity: Low
Attack requirements: Present
Impact type: Spoofing
Confidentiality · integrity · availability: High · None · None
Fix status: Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-601.

Summary

Sensitive Data Exposure vulnerability in benoitc hackney allows Retrieve Embedded Sensitive Data. The HTTP/3 redirect handler in src/hackney_h3.erl passes the original request headers unchanged to the redirect target without performing any cross-origin check. When a client issues an HTTP/3 request with follow_redirect enabled and includes Authorization or Cookie headers, a server responding with a 3xx redirect to a different host will cause the client to forward those credentials verbatim to the new origin. The main hackney.erl module has maybe_strip_auth_on_redirect/2 (guarded by the location_trusted option) to address CVE-2018-1000007, but hackney_h3.erl is missing this protection entirely. This issue affects hackney: from 3.1.1 before 4.0.1.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00372 31st percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix Fixed hackney (benoitc): 4.0.1hackney (Hex): 4.0.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
benoitc	hackney	3.1.1 to before 4.0.1	4.0.1	Patch available	CNA
—	hackney (Hex)	3.1.1 to before 4.0.1	4.0.1	Patch available	GHSA-h73q-4w9q-82h4

hackney Vendorbenoitc Affected 3.1.1 to before 4.0.1 Fixed in 4.0.1 Patch available CNA
hackney (Hex) Vendor— Affected 3.1.1 to before 4.0.1 Fixed in 4.0.1 Patch available GHSA-h73q-4w9q-82h4

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:benoitc:hackney::::::::	3.1.1 to before 4.0.1	Vulnerable	benoitc

cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:* Versions 3.1.1 to before 4.0.1 Vulnerable ·benoitc

Remediation

Fix · CNA hackney (benoitc) Fixed in 4.0.1
Fix · GHSA-h73q-4w9q-82h4 hackney (Hex) Fixed in 4.0.1 Advisory →

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

Release · 2026-05-25
benoitc hackney 4.0.1
10 records Highest priority Priority HIGH 6 HIGH, 4 MEDIUM
Other records, highest priority first
- TI-2026-34675 Unbounded memory consumption in WebSocket client in hackneyPriority HIGH 77
- TI-2026-34669 Atom table exhaustion via unrecognized URL schemes in hackneyPriority HIGH 77
- TI-2026-34668 Infinite loop in Alt-Svc header parser in hackneyPriority HIGH 77
Show all 10 records →

Timeline

2026-10-02 Threatist record created from CVE-2026-47070
2026-10-03 Alias added: GHSA-h73q-4w9q-82h4

References

Exploit 1

https://github.com/benoitc/hackney/security/advisories/GHSA-h73q-4w9q-82h4

Patch 3

Advisory 1

https://nvd.nist.gov/vuln/detail/CVE-2026-47070

Other 1

https://github.com/benoitc/hackney

TI-2026-34675 Unbounded memory consumption in WebSocket client in hackney CVSS 4.0HIGH 8.7
TI-2026-34669 Atom table exhaustion via unrecognized URL schemes in hackney CVSS 4.0HIGH 8.7
TI-2026-34668 Infinite loop in Alt-Svc header parser in hackney CVSS 4.0HIGH 8.7
TI-2026-34679 Unbounded body accumulation in HTTP/3 response loop in hackney CVSS 4.0HIGH 8.2
TI-2026-34673 SOCKS5 TLS upgrade ignores caller timeout in hackney CVSS 4.0HIGH 8.2
TI-2026-34674 CRLF injection in WebSocket upgrade request in hackney CVSS 4.0MEDIUM 6.9

See all 9 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences