{"answers":{"affected":"2 open source packages ship an affected version, including railties. It affects 3 products.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2019-5420 exists.","fix":"Upgrade railties to 5.2.2.1 or later.","what":"CVE-2019-5420 is a critical code injection vulnerability in Debian Debian Linux, published on 27 Mar 2019. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2019-5420 and fix it if it is affected.\n\nWhat it is: CVE-2019-5420 is a critical code injection vulnerability in Debian Debian Linux, published on 27 Mar 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2019-5420 exists.\n\nAffected packages and fixed versions:\n- railties (RubyGems): affected from 5.2.0; fixed in 5.2.2.1\n- railties (RubyGems): affected from 5.2.0; fixed in 5.2.2.1\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2019-5420/ (Markdown: https://insights.sbomify.com/CVE-2019-5420/index.md)","id":"CVE-2019-5420","markdown":"https://insights.sbomify.com/CVE-2019-5420/index.md","name":"CVE-2019-5420","record":{"aliases":["DEBIAN-CVE-2019-5420","GHSA-m42h-mh85-4qgc"],"analysis":{"component_type":"web_application","fix_type":"upgrade","impacts":["code_execution"],"network_reachable":"yes","non_default_config":true,"product_category":"Ruby on Rails framework","requires_auth":"none","summary":"Attackers can achieve remote code execution in Rails development mode by guessing the secret token and exploiting internal mechanisms.","user_interaction":"not_required","vuln_class":"code_injection"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"hackerone","cpe":[{"product":"debian_linux","vendor":"debian"},{"product":"fedora","vendor":"fedoraproject"},{"product":"rails","vendor":"rubyonrails"}],"cvss":{"score":9.8,"severity":"critical","source":"nvd","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-330","name":"Use of Insufficiently Random Values"},{"id":"CWE-77","name":"Improper Neutralization of Special Elements used in a Command"}],"description":"A remote code execution vulnerability in development mode Rails \u003c5.2.2.1, \u003c6.0.0.beta3 can allow an attacker to guess the automatically generated development mode secret token. This secret token can be used in combination with other Rails internals to escalate to a remote code execution exploit.","ecosystems":["RubyGems"],"exploits":{"exploitdb":1,"first_seen":"2019-03-13","github_poc":12,"max_poc_stars":8,"metasploit":1,"nuclei":0,"refs":[{"date":"2019-03-21T15:42:54Z","kind":"github_poc","ref":"https://github.com/knqyf263/CVE-2019-5420","stars":8,"title":"CVE-2019-5420 (Ruby on Rails)"},{"date":"2021-09-06T12:28:05Z","kind":"github_poc","ref":"https://github.com/j4k0m/CVE-2019-5420","stars":5,"title":"A vulnerability can allow an attacker to guess the automatically generated development mode secret token."},{"date":"2022-07-02T15:44:03Z","kind":"github_poc","ref":"https://github.com/laffray/ruby-RCE-CVE-2019-5420-","stars":5,"title":"Ruby反序列化命令执行漏洞（CVE-2019-5420）-vulfocus通关版"},{"date":"2021-05-11T11:32:18Z","kind":"github_poc","ref":"https://github.com/scumdestroy/CVE-2019-5420.rb","stars":3,"title":"POC Exploit written in Ruby"},{"date":"2022-03-14T17:29:47Z","kind":"github_poc","ref":"https://github.com/trickstersec/CVE-2019-5420","stars":1,"title":"Exploit for the Rails CVE-2019-5420"},{"date":"2025-02-10T15:24:55Z","kind":"github_poc","ref":"https://github.com/WildWestCyberSecurity/cve-2019-5420-POC","stars":1,"title":"cve-2019-5420 POC simple ruby script"},{"date":"2019-03-13","kind":"metasploit","ref":"exploit/multi/http/rails_double_tap","stars":null,"title":"Ruby On Rails DoubleTap Development Mode secret_key_base Vulnerability"},{"date":"2019-03-27T18:16:46Z","kind":"github_poc","ref":"https://github.com/cved-sources/cve-2019-5420","stars":0,"title":"cve-2019-5420"}],"tier":"weaponised"},"has_fix":true,"headline":"Use of Insufficiently Random Values in Railties Allows Remote Code Execution","id":"CVE-2019-5420","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"RubyGems","product":"debian:debian_linux","products":["debian:debian_linux","fedoraproject:fedora","rubyonrails:rails"],"type":"code_injection","year":"2019"},"n_packages":2,"n_references":5,"next":{"headline":"devise Time-of-check Time-of-use Race Condition vulnerability","id":"CVE-2019-5421"},"packages":[{"ecosystem":"RubyGems","fixed":["5.2.2.1"],"introduced":["5.2.0"],"last_affected":[],"package":"railties","purl":null,"source":"GHSA-m42h-mh85-4qgc"},{"ecosystem":"RubyGems","fixed":["5.2.2.1"],"introduced":["5.2.0"],"last_affected":[],"package":"railties","purl":"pkg:gem/railties","source":"GHSA-m42h-mh85-4qgc"}],"prev":{"headline":"Denial of Service Vulnerability in Action View","id":"CVE-2019-5419"},"products":["https://github.com/rails/rails"],"published":"2019-03-27","related":[{"cvss_score":10,"headline":"ProFTPD Improper Access Control","id":"CVE-2015-3306","kev_date_added":"2026-10-08","published":"2015-05-18"},{"cvss_score":9.9,"headline":"RoundCube Webmail Deserialization of Untrusted Data","id":"CVE-2025-49113","kev_date_added":"2026-02-20","published":"2025-06-02"},{"cvss_score":9.8,"headline":"GNU InetUtils Argument Injection","id":"CVE-2026-24061","kev_date_added":"2026-01-26","published":"2026-01-21"},{"cvss_score":9.8,"headline":"Linux Kernel Improper Check for Unusual or Exceptional Conditions","id":"CVE-2025-39682","kev_date_added":"2026-09-18","published":"2025-09-05"},{"cvss_score":9.8,"headline":"Mozilla Firefox Use-After-Free","id":"CVE-2024-9680","kev_date_added":"2024-10-15","published":"2024-10-09"},{"cvss_score":9.8,"headline":"RARLAB UnRAR Directory Traversal","id":"CVE-2022-30333","kev_date_added":"2022-08-09","published":"2022-05-09"},{"cvss_score":9.8,"headline":"Roundcube Webmail SQL Injection","id":"CVE-2021-44026","kev_date_added":"2023-06-22","published":"2021-11-19"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"},{"class":"attribution","licence":"BSD-3-Clause","name":"Metasploit"},{"class":"open","licence":"CC0","name":"PoC-in-GitHub"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2024-08-04","vendors":["Rails"]},"summary":"Attackers can achieve remote code execution in Rails development mode by guessing the secret token and exploiting internal mechanisms.","url":"https://insights.sbomify.com/CVE-2019-5420/"}