6.1

CVE-2026-47070: HTTP/3 redirect handler leaks Authorization and Cookie headers to cross-origin redirect target in hackney

Analyzed
Published 25-05-2026Last modified 27-05-2026

Vulnerability summary

CVE-2026-47070 is a medium (CVSS 6.1) URL Redirection to Untrusted Site vulnerability in benoitc hackney. EPSS estimates a 0.37% chance of exploitation in the next 30 days, higher than 31.2% of scored vulnerabilities. 1 public exploit is recorded.

Priority
Routine

Not severe (CVSS 6, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
6.1/10
010
Medium · v3.1 (NVD)
EPSS score
0.37%
0%100%
Low · +0.02 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits1github

Timeline

  1. 25-05-2026
    PublishedVulnerability first disclosed.
  2. 27-05-2026
    Last modifiedVulnerability information updated.

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.

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

0.37%

Chance of exploitation in the next 30 days

Percentile

31%

Versus all other CVEs

30-day change

Increase +0.02 pp

From 0.35% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

1 found
  • githubUnverified

    Hackney

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, user interaction (CVSS vector). Other conditions: not stated in public data.

Benoitc1 product
  • hackney≥ e61b7d04b7826847e1efe614106ef4d580c78eab, < c58d5b50bade146360b85caf3dc8065807b08246 | ≥ 3.1.1, < 4.0.1

1 vendor · 1 product

References

4 links