CVE-2026-47070

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

MEDIUM
6.1
CVSS Score
Published: May 25, 2026 at 02:00 PM UTC
Updated: July 24, 2026 at 10:23 AM UTC
1 product affected across 1 vendorHackney

Using hackney by benoitc?

Get instant alerts when new vulnerabilities affect hackney - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
MEDIUM6.1
Exploit prediction
EPSS 0.4%
SSVC
PoC

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

3.1.1 ≤ v < 4.0.13.1.1e61b7d04b7826847e1efe614106ef4d580c78eab
Vendor states this is fixed in c58d5b50bade146360b85caf3dc8065807b08246 (fixed)
Affected range stops below 4.0.1, so it looks safe — our inference, not a vendor statement

References (4)

Vendor AdvisoryRelatedExploitPatch
Source: cverecord
https://github.com/benoitc/hackney/security/advisories/GHSA-h73q-4w9q-82h4
RelatedPatchThird Party Advisory
Source: cverecord
https://cna.erlef.org/cves/CVE-2026-47070.html
RelatedPatchThird Party Advisory
Source: cverecord
https://osv.dev/vulnerability/EEF-CVE-2026-47070

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-601

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card