CVE-2019-5418: Rails Ruby on Rails Path Traversal Vulnerability
Rails · Ruby on Rails · NVD published 2019-03-27 · posted 2025-07-07 · last modified 2026-06-17
What it is
There is a File Content Disclosure vulnerability in Action View <5.2.2.1, <5.1.6.2, <5.0.7.2, <4.2.11.1 and v3 where specially crafted accept headers can cause contents of arbitrary files on the target system's filesystem to be exposed.
| Weakness | CWE-22 |
|---|---|
| CVSS vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N (source: [email protected]) |
| CISA due date | 2025-07-28 (for US federal agencies under BOD; a good deadline for everyone) |
| ATT&CK tactics | Initial Access → Discovery |
Exploitation evidence
First exploit evidence seen: 2019-03-21 (earliest date across the sources below).
Exploited in the wild
- CISA KEV: listed since 2025-07-07. Source
Public exploit code
Metasploit
auxiliary/gather/rails_doubletap_file_read: Ruby On Rails File Content Disclosure ('doubletap')
Exploit-DB
- EDB-46585: Rails 5.2.1 - Arbitrary File Content Disclosure (2019-03-21)
GitHub proof-of-concept repositories
12 public repositories from 11 accounts, first seen 2019-03-27. Most starred: mpgn/CVE-2019-5418 (201 stars), view repository.
Verify before running: public PoCs can be malicious. Read the code and only run it in an isolated lab. A PoC means exploit code is public, not that this CVE is exploited in the wild.
Sources: CISA KEV · Rapid7 Metasploit Framework module metadata · Exploit-DB (OffSec) · nomi-sec/PoC-in-GitHub.
Defend the Chain
The attack chain for CVE-2019-5418 laid across the MITRE ATT&CK Enterprise tactics. Solid cards come from the MITRE CTID KEV mappings; dashed cards are inferred by CVERadar from the CWE or description. Correct defences are real ATT&CK mitigations for that technique.
Pick a red technique card on the board, then choose the defence that stops it.
Defend against T1190 Exploit Public-Facing Application Inferred
Inferred from CWE CWE-22
How to fix it
CISA required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. (source: CISA KEV)
Fixed versions
- rubyonrails rails: upgrade to 4.2.11.1 or later (affected from 3.0.0)
- rubyonrails rails: upgrade to 5.0.7.2 or later (affected from 5.0.0)
- rubyonrails rails: upgrade to 5.1.6.2 or later (affected from 5.1.0)
- rubyonrails rails: upgrade to 5.2.2.1 or later (affected from 5.2.0)
Derived from the NVD CPE configuration (versionEndExcluding / versionEndIncluding). Always confirm with the vendor advisory.
Vendor advisories and patches
- https://web.archive.org/web/20190313201629/https://weblog.rubyonrails.org/2019/3/13/Rails-4-2-5-1-5-1-6-2-have-been-released/ (CISA KEV notes)
- http://www.openwall.com/lists/oss-security/2019/03/22/1 (Mailing List, Mitigation, Patch, Third Party Advisory)
- https://weblog.rubyonrails.org/2019/3/13/Rails-4-2-5-1-5-1-6-2-have-been-released/ (Broken Link, Patch, Vendor Advisory)
MITRE ATT&CK mitigations for this chain
- M1048 Application Isolation and Sandboxing (for T1190) : Application isolation will limit what other processes and system features the exploited target can access.
- M1037 Filter Network Traffic (for T1190) : Restrict outbound network traffic from public-facing servers to prevent unauthorized connections from initiating communications with attacker-controlled infrastructure. While this may not prevent the initial exploitation, it limits the attacker's ability to verify and control the compromised server post-exploit, reduci
- M1030 Network Segmentation (for T1190) : Segment externally facing servers and services from the rest of the network with a DMZ or on separate hosting infrastructure.
- M1016 Vulnerability Scanning (for T1190) : Regularly scan externally facing systems for vulnerabilities and establish procedures to rapidly patch systems when critical vulnerabilities are discovered through scanning and through public disclosure.
- M1026 Privileged Account Management (for T1190) : Use least privilege for service accounts will limit what permissions the exploited process gets on the rest of the system.
- M1050 Exploit Protection (for T1190) : Web Application Firewalls may be used to limit exposure of applications to prevent exploit traffic from reaching the application.
- M1035 Limit Access to Resource Over Network (for T1190) : Ensure that all publicly exposed services are actually intended to be so, and restrict access to any that should only be available internally.
- M1051 Update Software (for T1190) : Update software regularly by employing patch management for externally exposed applications.
Detection Generic guidance
- Initial Access: Alert on unusual requests to the affected service (odd paths, oversized payloads, exploit strings) in WAF, reverse-proxy and application logs.
- Discovery: Look for directory listing, file enumeration and reconnaissance commands from service accounts.
Response checklist Generic guidance
- Inventory: find every instance of the affected product and version (include internet-facing and forgotten ones).
- Patch or mitigate per the vendor advisory; if you cannot patch, remove internet exposure or apply the vendor workaround.
- Assume compromise if the system was exposed before patching: hunt for the indicators in the advisory and review logs back to the disclosure date.
- Rotate credentials and secrets stored on or used by the affected system if compromise cannot be ruled out.
Sources
- NVD: CVE-2019-5418
- CVE.org record
- CISA Known Exploited Vulnerabilities catalog
- FIRST EPSS (2026-10-24)
- http://lists.opensuse.org/opensuse-security-announce/2019-05/msg00011.html (Mailing List, Third Party Advisory)
- http://packetstormsecurity.com/files/152178/Rails-5.2.1-Arbitrary-File-Content-Disclosure.html (Exploit, Third Party Advisory, VDB Entry)
- https://access.redhat.com/errata/RHSA-2019:0796 (Third Party Advisory)
- https://access.redhat.com/errata/RHSA-2019:1147 (Third Party Advisory)
- https://access.redhat.com/errata/RHSA-2019:1149 (Third Party Advisory)
- https://access.redhat.com/errata/RHSA-2019:1289 (Third Party Advisory)
- https://groups.google.com/forum/#%21topic/rubyonrails-security/pFRKI96Sm8Q (Permissions Required)
- https://lists.debian.org/debian-lts-announce/2019/03/msg00042.html (Mailing List, Third Party Advisory)
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Y43636TH4D6T46IC6N2RQVJTRFJAAYGA/ (Third Party Advisory)
- https://www.exploit-db.com/exploits/46585/ (Exploit, Third Party Advisory, VDB Entry)
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-5418 (US Government Resource)