CVE-2019-18409 json
Ruby_parser-legacy Incorrect Permission Assignment for Critical Resource
published 2019-10-24 7 y ago modified 2026-06-17 4 mo ago also GHSA-hhwc-8g49-j8jx , EUVD-2019-0704
- cvss
- 7.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 26%
- public exploits
- 0
- none known
Summary
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.
Exploit prediction
0.33% chance of exploitation in the next 30 days, higher than 26% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/zenspider/ruby_parser-legacy/issues/1 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 4.6 | AV:L/AC:L/Au:N/C:P/I:P/A:P |
| GitHub | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| rubygems | ruby_parser-legacy | <=1.0.0 |
no fix listed |
Classification
- Weakness
-
- CWE-732 Incorrect Permission Assignment for Critical Resource
References
-
github.com
/zenspider/ruby_parser-legacy/issues/1
web, exploit, issue-tracking, third-party-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2019-18409
advisory
-
brakemanscanner.org
/blog/2019/10/14/brakeman-4-dot-7-dot-1-released
web
-
github.com
/rubysec/ruby-advisory-db/blob/master/gems/brakeman/CVE-2019-18409.yml
web
-
github.com
/zenspider/ruby_parser-legacy
package
Sources
- CVE List CVE-2019-18409
- GitHub Advisory GHSA-hhwc-8g49-j8jx
- NVD CVE-2019-18409
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.