Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2026-47076

26
FAUCET Score

Interpretation Conflict vulnerability in benoitc hackney allows Server Side Request Forgery. hackney_url:normalize/2 URL-decodes the host component after the URL has been parsed into a #hackney_url{} record. OTP's uri_string:parse/1 and inet:parse_address/1 do not decode percent-escapes in the host, so a URL such as http://%31%32%37%2E%30%2E%30%2E%31/ is seen by a caller's allowlist validator with host %31%32%37%2E%30%2E%30%2E%31 (not an IP address), which passes the allowlist check. hackney's normalizer then decodes the host to 127.0.0.1 and opens a TCP connection to loopback. Because hackney:request/5 always calls hackney_url:normalize/2 with no opt-out, every request that takes a binary or list URL is affected. The same technique reaches cloud instance metadata services (169.254.169.254), RFC1918 networks, and any admin interface listening on localhost. This issue affects hackney: from 0.13.0 before 4.0.1.

First published: May 25, 2026Last modified: May 25, 2026

Impacted Technologies

VendorProductVersion(s)CPE
>= 0.13.0, < 4.0.1CPE matchmatch criteria
cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 4.0

6.9MEDIUM

CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/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

Attack Vector
LOCAL
Attack Complexity
LOW
Attack Requirements
PRESENT
Privileges Required
NONE
User Interaction
NONE
VS Confidentiality
HIGH
VS Integrity
NONE
VS Availability
NONE
SS Confidentiality
HIGH
SS Integrity
NONE
SS Availability
NONE
Exploit Maturity
NOT_DEFINED
CvssVersion
4.0

Exploit Intelligence

EPSS Score
0.23%
Probability of exploitation in next 30 days
EPSS Percentile
13.8%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
This CVE's current EPSS score of 0.0023 is in the 61st percentile among its peer group of 15,938 CVEs.

Social Chatter

No social media mentions found for this CVE.

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.0 Bluesky, 0.0 Mastodon, and 0.1 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (2)

erlangpatch availablevia ghsa
Product: hackneyFixed in: 4.0.1
github_advisorypatch availablevia nvd_reference
View patch

Vendor Advisories (1)

erlangGHSA-pj7v-xfvx-wmjqmedium

Hackney has SSRF allowlist bypass in hackney_url:normalize/2 via percent-encoded host

Jun 26, 2026

References

cna.erlef.org / cves/CVE-2026-47076.html
PatchThird Party Advisory
github.com / benoitc/hackney/commit/452620a92ec1da2e6b4862a049a2a4f04b42068f
Patch
github.com / benoitc/hackney/security/advisories/GHSA-pj7v-xfvx-wmjq
ExploitPatchVendor Advisory
osv.dev / vulnerability/EEF-CVE-2026-47076
PatchThird Party Advisory