Skip to content
Fencer Vulns
high 7.1

CVE-2024-32970 json

Cross-site Scripting (XSS) possible with maliciously formed HTML attribute names and values in Phlex

published 2024-04-30 2 y ago modified 2026-09-10 1 mo ago also EUVD-2024-1557 , GHSA-9p57-h987-4vgx

cvss
7.1
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.7%
EPSS 0.7% chance of exploitation in 30 days, percentile 53%
public exploits
0
none known

Summary

Phlex is a framework for building object-oriented views in Ruby. In affected versions there is a potential cross-site scripting (XSS) vulnerability that can be exploited via maliciously crafted user data. Since the last two vulnerabilities https://github.com/phlex-ruby/phlex/security/advisories/GHSA-242p-4v39-2v8g and https://github.com/phlex-ruby/phlex/security/advisories/GHSA-g7xq-xv8c-h98c, we have invested in extensive browser tests. It was these new tests that helped us uncover these issues. As of now the project exercises every possible attack vector the developers can think of — including enumerating every ASCII character, and we run these tests in Chrome, Firefox and Safari. Additionally, we test against a list of 6613 known XSS payloads (see: payloadbox/xss-payload-list). The reason these issues were not detected before is the escapes were working as designed. However, their design didn't take into account just how recklessly permissive browsers are when it comes to executing unsafe JavaScript via HTML attributes. If you render an `<a>` tag with an `href` attribute set to a user-provided link, that link could potentially execute JavaScript when clicked by another user. If you splat user-provided attributes when rendering any HTML or SVG tag, malicious event attributes could be included in the output, executing JavaScript when the events are triggered by another user. Patches are available on RubyGems for all minor versions released in the last year. Users are advised to upgrade. Users unable to upgrade should configure a Content Security Policy that does not allow `unsafe-inline` which would effectively prevent this vulnerability from being exploited. Users who upgrade are also advised to configure a Content Security Policy header that does not allow `unsafe-inline`.

Patch / fix

  • rubygems phlex 1.9.3, 1.10.2
  • phlex phlex 1.9.3, 1.10.2

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
2 y ago

Exploit prediction

0.71% chance of exploitation in the next 30 days, higher than 53% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N
GitHub 3.1 7.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N

Affected packages

ecosystem package affected fixed in
rubygems phlex
<1.9.3
>=1.10.0, <1.10.2
1.9.3
1.10.2

Affected products

  • phlex-ruby phlex

Classification

Weakness
  • CWE-79 Improper Neutralization of Input During Web Page Generation

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.