CVE-2019-18978
It allows ../ directory traversal to access private resources because resource matching does not ensure that pathnames are in a canonical format.
Does this matter?
Lower severity and a low EPSS score (2.46%). Track it; it rarely justifies an emergency change on its own.
Description
An issue was discovered in the rack-cors (aka Rack CORS Middleware) gem before 1.0.4 for Ruby. It allows ../ directory traversal to access private resources because resource matching does not ensure that pathnames are in a canonical format.
- CVSS 3.1
- 5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
- EPSS
- 2.46% probability · 84th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-22
- Affected
- rack-cors project/rack-cors · debian/debian linux · canonical/ubuntu linux
- Source
- cve@mitre.org
EPSS 2.5% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/cyu/rack-cors/commit/e4d4fc362a4315808927011cbe5afcfe5486f17dPatch, Third Party Advisory
- https://github.com/cyu/rack-cors/compare/v1.0.3...v1.0.4Patch, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2020/02/msg00004.htmlMailing List, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2020/10/msg00000.htmlMailing List, Third Party Advisory
- https://usn.ubuntu.com/4571-1/Third Party Advisory
- https://www.debian.org/security/2021/dsa-4918Third Party Advisory
- https://github.com/cyu/rack-cors/commit/e4d4fc362a4315808927011cbe5afcfe5486f17dPatch, Third Party Advisory
- https://github.com/cyu/rack-cors/compare/v1.0.3...v1.0.4Patch, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2020/02/msg00004.htmlMailing List, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2020/10/msg00000.htmlMailing List, Third Party Advisory
- https://usn.ubuntu.com/4571-1/Third Party Advisory
- https://www.debian.org/security/2021/dsa-4918Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.