What is CVE-2019-18409?

CVE-2019-18409 is a high-severity vulnerability in Zenspider Ruby Parser-Legacy, classified under Incorrect Permission Assignment for Critical Resource. CVSS score: 7.8/10. Published 2019-10-24.

How severe is CVE-2019-18409?

High severity. CVSS v3 base score is 7.8 out of 10.

Vulnerability in Zenspider Ruby Parser-Legacy

CVE-2019-18409

The ruby_parser-legacy (aka legacy) gem 1.0.0 for Ruby allows local privilege escalation because of world-writable files. For example, if the brakeman gem (which has a legacy dependency) 4.5.0 through 4.7.0 is used, a local user can insert malicious code into the ruby_parser-legacy-1.0.0/lib/ruby_parser/legacy/ruby_parser.rb file.

Published 2019-10-24 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.003 (24.0th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 24th percentile — 24.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Zenspider Ruby Parser-Legacy — versions 1.0.0

Weakness classification (CWE)

CWE-732 — Incorrect Permission Assignment for Critical Resource

References

github.com/zenspider/ruby_parser-legacy/issues/1 (Exploit, Third Party Advisory, Issue Tracking)

Frequently asked questions

What is CVE-2019-18409?: CVE-2019-18409 is a high-severity vulnerability in Zenspider Ruby Parser-Legacy, classified under Incorrect Permission Assignment for Critical Resource. CVSS score: 7.8/10. Published 2019-10-24.
How severe is CVE-2019-18409?: High severity. CVSS v3 base score is 7.8 out of 10.