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-2021-29479

21
FAUCET Score

CVE-2021-29479 describes a cache poisoning vulnerability in Ratpack, a web application toolkit, affecting versions prior to 1.9.0. An attacker can manipulate the X-Forwarded-Host header to poison a fronting cache, leading to malicious redirects. The vulnerability has a CVSS score of 6.1 (Medium), indicating a network-based attack with low complexity, requiring user interaction, and potentially impacting confidentiality and integrity. There is currently no evidence of active exploitation, public exploit code (Metasploit, Nuclei, ExploitDB), or significant community discussion or media coverage.

Impacted Technologies

VendorProductVersion(s)CPE
< 1.9.0CPE matchmatch criteria
cpe:2.3:a:ratpack_project:ratpack:*:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

7.0HIGH

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

Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
LOW
Integrity Impact
HIGH
Availability Impact
LOW
Exploitability Score
2.2
Impact Score
4.7
CvssVersion
3.1

Exploit Intelligence

EPSS Score
0.86%
Probability of exploitation in next 30 days
EPSS Percentile
54.7%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
This CVE's current EPSS score of 0.0086 is in the 65th percentile among its peer group of 26,234 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 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 (1)

mavenpatch availablevia ghsa
Product: io.ratpack:ratpack-coreFixed in: 1.9.0

Vendor Advisories (1)

mavenGHSA-w6rq-6h34-vh7qhigh

Cached redirect poisoning via X-Forwarded-Host header

Jul 1, 2021

References

github.com / ratpack/ratpack/security/advisories/GHSA-w6rq-6h34-vh7q
Third Party Advisory
portswigger.net / web-security/web-cache-poisoning
ExploitThird Party Advisory