{"answers":{"affected":"35 open source packages ship an affected version, including symfony/security, symfony and lexik/jwt-authentication-bundle. It affects 2 products.","exploited":"There is no known exploitation of CVE-2021-21424 in the wild and no public exploit code.","fix":"Upgrade symfony/security to a fixed version for your release line: 3.4.49, 4.4.24 or 5.2.8.","what":"CVE-2021-21424 is a medium-severity vulnerability in Fedoraproject Fedora, published on 13 May 2021. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2021-21424 and fix it if it is affected.\n\nWhat it is: CVE-2021-21424 is a medium-severity vulnerability in Fedoraproject Fedora, published on 13 May 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2021-21424 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- symfony/security (Packagist): affected from 2.8.0; fixed in 3.4.49\n- symfony/security (Packagist): affected from 2.8.0; fixed in 3.4.49\n- symfony/security (Packagist): affected from 4.0.0; fixed in 4.4.24\n- symfony/security (Packagist): affected from 4.0.0; fixed in 4.4.24\n- symfony/security (Packagist): affected from 5.0.0; fixed in 5.2.8\n- symfony/security (Packagist): affected from 5.0.0; fixed in 5.2.8\n- symfony (Bitnami): affected from 2.8.0; fixed in 3.4.48, 4.4.23, 5.2.8\n- lexik/jwt-authentication-bundle (Packagist): affected from 2.0.0; fixed in 2.10.7\n- lexik/jwt-authentication-bundle (Packagist): affected from 2.0.0; fixed in 2.10.7\n- lexik/jwt-authentication-bundle (Packagist): affected from 2.11.0; fixed in 2.11.3\n- lexik/jwt-authentication-bundle (Packagist): affected from 2.11.0; fixed in 2.11.3\n- symfony/maker-bundle (Packagist): affected from 1.27.0; fixed in 1.29.2\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-2021-21424/ (Markdown: https://insights.sbomify.com/CVE-2021-21424/index.md)","id":"CVE-2021-21424","markdown":"https://insights.sbomify.com/CVE-2021-21424/index.md","name":"CVE-2021-21424","record":{"aliases":["BIT-symfony-2021-21424","DEBIAN-CVE-2021-21424","GHSA-5pv8-ppvj-4h68","UBUNTU-CVE-2021-21424"],"analysis":{"component_type":"library","fix_type":"patch","impacts":["data_read"],"network_reachable":"yes","non_default_config":false,"product_category":"PHP web framework","requires_auth":"none","summary":"Attackers can enumerate valid usernames via inconsistent error responses in Symfony's user switching feature, exposing user existence information.","user_interaction":"not_required","vuln_class":"information_disclosure"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"fedora","vendor":"fedoraproject"},{"product":"symfony","vendor":"sensiolabs"}],"cvss":{"score":5.3,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","version":"3.1"},"cwes":[{"id":"CWE-203","name":"Observable Discrepancy"},{"id":"CWE-200","name":"Exposure of Sensitive Information to an Unauthorized Actor"}],"description":"Symfony is a PHP framework for web and console applications and a set of reusable PHP components. The ability to enumerate users was possible without relevant permissions due to different handling depending on whether the user existed or not when attempting to use the switch users functionality. We now ensure that 403s are returned whether the user exists or not if a user cannot switch to a user or if the user does not exist. The patch for this issue is available for branch 3.4.","ecosystems":["Bitnami","Packagist"],"exploits":{"exploitdb":0,"first_seen":"2025-04-14","github_poc":2,"max_poc_stars":0,"metasploit":0,"nuclei":0,"refs":[{"date":"2025-04-14T21:08:42Z","kind":"github_poc","ref":"https://github.com/moften/CVE-2021-21424","stars":0,"title":" El WebProfiler de Symfony expone rutas internas del servidor si no está deshabilitado en producción"},{"date":"2025-05-07T23:07:11Z","kind":"github_poc","ref":"https://github.com/moften/Symfony-CVE-Scanner-PoC-","stars":0,"title":" CVE-2021-21424 - CRLF Injection - CVE-2021-41268 - Host Header Injection - CVE-2022-24894 - WebProfiler abierto - CVE-2019-10909 - Directory Traversal"}],"tier":"poc_unverified"},"has_fix":true,"headline":"Prevent user enumeration using Guard or the new Authenticator-based Security","id":"CVE-2021-21424","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Bitnami","product":"fedoraproject:fedora","products":["fedoraproject:fedora","sensiolabs:symfony"],"type":"information_disclosure","year":"2021"},"n_packages":35,"n_references":7,"next":{"headline":"Unauthenticated Arbitrary YAML Write/Update leads to Code Execution","id":"CVE-2021-21425"},"packages":[{"ecosystem":"Bitnami","fixed":["3.4.48","4.4.23","5.2.8"],"introduced":["2.8.0","4.0.0","5.0.0"],"last_affected":[],"package":"symfony","purl":"pkg:bitnami/symfony","source":"BIT-symfony-2021-21424"},{"ecosystem":"Packagist","fixed":["2.10.7"],"introduced":["2.0.0"],"last_affected":[],"package":"lexik/jwt-authentication-bundle","purl":null,"source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["2.10.7"],"introduced":["2.0.0"],"last_affected":[],"package":"lexik/jwt-authentication-bundle","purl":"pkg:composer/lexik/jwt-authentication-bundle","source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["2.11.3"],"introduced":["2.11.0"],"last_affected":[],"package":"lexik/jwt-authentication-bundle","purl":null,"source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["2.11.3"],"introduced":["2.11.0"],"last_affected":[],"package":"lexik/jwt-authentication-bundle","purl":"pkg:composer/lexik/jwt-authentication-bundle","source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["1.29.2"],"introduced":["1.27.0"],"last_affected":[],"package":"symfony/maker-bundle","purl":null,"source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["1.29.2"],"introduced":["1.27.0"],"last_affected":[],"package":"symfony/maker-bundle","purl":"pkg:composer/symfony/maker-bundle","source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["1.31.1"],"introduced":["1.30.0"],"last_affected":[],"package":"symfony/maker-bundle","purl":null,"source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["1.31.1"],"introduced":["1.30.0"],"last_affected":[],"package":"symfony/maker-bundle","purl":"pkg:composer/symfony/maker-bundle","source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["3.4.49"],"introduced":["2.8.0"],"last_affected":[],"package":"symfony/security","purl":null,"source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["3.4.49"],"introduced":["2.8.0"],"last_affected":[],"package":"symfony/security","purl":"pkg:composer/symfony/security","source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["4.4.24"],"introduced":["4.0.0"],"last_affected":[],"package":"symfony/security","purl":null,"source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["4.4.24"],"introduced":["4.0.0"],"last_affected":[],"package":"symfony/security","purl":"pkg:composer/symfony/security","source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["5.2.8"],"introduced":["5.0.0"],"last_affected":[],"package":"symfony/security","purl":null,"source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["5.2.8"],"introduced":["5.0.0"],"last_affected":[],"package":"symfony/security","purl":"pkg:composer/symfony/security","source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["3.4.48"],"introduced":["2.8.0"],"last_affected":[],"package":"symfony/security-core","purl":null,"source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["3.4.48"],"introduced":["2.8.0"],"last_affected":[],"package":"symfony/security-core","purl":"pkg:composer/symfony/security-core","source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["4.4.23"],"introduced":["4.0.0"],"last_affected":[],"package":"symfony/security-core","purl":null,"source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["4.4.23"],"introduced":["4.0.0"],"last_affected":[],"package":"symfony/security-core","purl":"pkg:composer/symfony/security-core","source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["5.2.8"],"introduced":["5.0.0"],"last_affected":[],"package":"symfony/security-core","purl":null,"source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["5.2.8"],"introduced":["5.0.0"],"last_affected":[],"package":"symfony/security-core","purl":"pkg:composer/symfony/security-core","source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["3.4.48"],"introduced":["2.8.0"],"last_affected":[],"package":"symfony/security-guard","purl":null,"source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["3.4.48"],"introduced":["2.8.0"],"last_affected":[],"package":"symfony/security-guard","purl":"pkg:composer/symfony/security-guard","source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["4.4.23"],"introduced":["4.0.0"],"last_affected":[],"package":"symfony/security-guard","purl":null,"source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["4.4.23"],"introduced":["4.0.0"],"last_affected":[],"package":"symfony/security-guard","purl":"pkg:composer/symfony/security-guard","source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["5.2.8"],"introduced":["5.0.0"],"last_affected":[],"package":"symfony/security-guard","purl":null,"source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["5.2.8"],"introduced":["5.0.0"],"last_affected":[],"package":"symfony/security-guard","purl":"pkg:composer/symfony/security-guard","source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["5.2.8"],"introduced":["5.1.0"],"last_affected":[],"package":"symfony/security-http","purl":null,"source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["5.2.8"],"introduced":["5.1.0"],"last_affected":[],"package":"symfony/security-http","purl":"pkg:composer/symfony/security-http","source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["3.4.49"],"introduced":["2.8.0"],"last_affected":[],"package":"symfony/symfony","purl":null,"source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["3.4.49"],"introduced":["2.8.0"],"last_affected":[],"package":"symfony/symfony","purl":"pkg:composer/symfony/symfony","source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["4.4.24"],"introduced":["4.0.0"],"last_affected":[],"package":"symfony/symfony","purl":null,"source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["4.4.24"],"introduced":["4.0.0"],"last_affected":[],"package":"symfony/symfony","purl":"pkg:composer/symfony/symfony","source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["5.2.9"],"introduced":["5.0.0"],"last_affected":[],"package":"symfony/symfony","purl":null,"source":"GHSA-5pv8-ppvj-4h68"},{"ecosystem":"Packagist","fixed":["5.2.9"],"introduced":["5.0.0"],"last_affected":[],"package":"symfony/symfony","purl":"pkg:composer/symfony/symfony","source":"GHSA-5pv8-ppvj-4h68"}],"prev":{"headline":"Exposure of Version-Control Repository to an Unauthorized Control Sphere in projen","id":"CVE-2021-21423"},"products":["symfony"],"published":"2021-05-13","related":[{"cvss_score":9.8,"headline":"PHP-CGI OS Command Injection","id":"CVE-2024-4577","kev_date_added":"2024-06-12","published":"2024-06-09"},{"cvss_score":9.8,"headline":"Grafana Authentication Bypass","id":"CVE-2021-39226","kev_date_added":"2022-08-25","published":"2021-10-05"},{"cvss_score":9.8,"headline":"VMware ESXi and Horizon DaaS OpenSLP Heap-Based Buffer Overflow","id":"CVE-2019-5544","kev_date_added":"2021-11-03","published":"2019-12-06"},{"cvss_score":9.6,"headline":"Google Chromium V8 Type Confusion","id":"CVE-2024-4947","kev_date_added":"2024-05-20","published":"2024-05-15"},{"cvss_score":9.6,"headline":"Google Chromium Visuals Use-After-Free","id":"CVE-2024-4671","kev_date_added":"2024-05-13","published":"2024-05-09"},{"cvss_score":9.6,"headline":"Google Chromium Mojo Insufficient Data Validation","id":"CVE-2022-3075","kev_date_added":"2022-09-08","published":"2022-09-26"},{"cvss_score":9.6,"headline":"Google Chromium Indexed DB API Use-After-Free","id":"CVE-2021-30633","kev_date_added":"2021-11-03","published":"2021-10-08"}],"sources":[{"class":"attribution","licence":"Apache-2.0","name":"Bitnami","prefix":"BIT"},{"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":"open","licence":"CC0","name":"PoC-in-GitHub"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2024-08-03","vendors":["symfony"]},"summary":"Attackers can enumerate valid usernames via inconsistent error responses in Symfony's user switching feature, exposing user existence information.","url":"https://insights.sbomify.com/CVE-2021-21424/"}