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-2017-11173

29
FAUCET Score

CVE-2017-11173 describes a missing anchor in the regex generation of rack-cors before version 0.4.1, affecting Debian Linux and rack-cors projects. This flaw allows a malicious third-party site to bypass intended CORS restrictions by crafting domain names that appear to be subdomains or variations of trusted ones, such as example.com.example.net. With a CVSS score of 8.8 (High), this vulnerability presents a significant risk, as it can lead to high impact on confidentiality, integrity, and availability with low attack complexity and no user interaction required. Currently, there is no evidence of active exploitation, public exploit code (Metasploit, Nuclei, ExploitDB), or significant community discussion or media coverage surrounding this CVE.

Impacted Technologies

VendorProductVersion(s)CPE
< 0.4.1CPE matchmatch criteria
cpe:2.3:a:rack-cors_project:rack-cors:*:*:*:*:*:ruby:*:*
9.0CPE matchmatch criteria
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

8.8HIGH

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

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
Exploitability Score
2.8
Impact Score
5.9
CvssVersion
3.1

Exploit Intelligence

EPSS Score
2.34%
Probability of exploitation in next 30 days
EPSS Percentile
81.9%
Percentile rank of EPSS score among Peer Group
As of 2026-07-25
Model: v2026.06.15
This CVE's current EPSS score of 0.0234 is in the 81st percentile among its peer group of 14,848 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.2 Bluesky, 0.1 Mastodon, and 0.2 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.1 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (2)

github_advisorypatch availablevia nvd_reference
View patch
rubygemspatch availablevia ghsa
Product: rack-corsFixed in: 0.4.1

Vendor Advisories (1)

rubygemsGHSA-2j9c-9vmv-7m39high

Missing Regex anchor in Rack-Cors allows malicious third party site to perform CORS request

Jul 31, 2018

References

seclists.org / fulldisclosure/2017/Jul/22
Mailing ListThird Party Advisory
github.com / cyu/rack-cors/commit/42ebe6caa8e85ffa9c8a171bda668ba1acc7a5e6
PatchThird Party Advisory
packetstormsecurity.com / files/143345/rack-cors-Missing-Anchor.html
Third Party AdvisoryVDB Entry
debian.org / security/2017/dsa-3931
Third Party Advisory