HackneyApplication · Benoitc

CVE-2026-47070

MEDIUM · 6.1 CVSS v3.1 Published 2026-05-25
Fix available
A fix is available. Upgrade to 4.0.1 or later.
See remediation →
68/100
Remediation priority · Elevated
Public exploit Remotely reachable No privileges Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis
How this class of weakness works · CWE-601

The application redirects the browser to a URL taken from user input without validating it, so an attacker can craft a link on your trusted domain that quietly bounces victims to a malicious site. It is a staple of phishing and token theft. The fix is to allow-list redirect destinations or use indirect reference keys, never a raw user-supplied URL.

General guidance for the open redirect class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
HackneyApplication
Affected:>= 3.1.1, < 4.0.1

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 4.0.1 or later
Fixed in 4.0.1
Vendor patch cna.erlef.org →
Recommended fix High confidence

hackney version 4.0.1 or later

  1. Identify your current hackney version in your Erlang/Elixir project (e.g., via rebar3 or Mix deps)
  2. Update your project dependency to use hackney version 4.0.1 or later
  3. Run your build tool to fetch and compile the new version (e.g., rebar3 compile or mix deps.update hackney)
  4. Verify the fix by reviewing src/hackney_h3.erl in the new version to confirm maybe_strip_auth_on_redirect/2 or equivalent cross-origin header stripping is implemented
  5. Test your application's redirect-handling code to ensure credentials are properly stripped when redirecting to untrusted origins
Caveat Version 4.0.1 may include other breaking changes; review the changelog for Erlang/OTP compatibility and API modifications

Generated from the published advisory — verify against the referenced sources before acting.

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $900. Get the upgrade done

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-47070 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-47070 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data