{"answers":{"affected":"8 open source packages ship an affected version, including symfony/security-http and symfony/symfony. It affects 1 product.","exploited":"There is no known exploitation of CVE-2019-18886 in the wild and no public exploit code.","fix":"Upgrade symfony/security-http to a fixed version for your release line: 4.2.12 or 4.3.8.","what":"CVE-2019-18886 is a medium-severity vulnerability in Sensiolabs Symfony, published on 21 Nov 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-2019-18886 and fix it if it is affected.\n\nWhat it is: CVE-2019-18886 is a medium-severity vulnerability in Sensiolabs Symfony, published on 21 Nov 2019. 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-2019-18886 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- symfony/security-http (Packagist): affected from 4.1.0; fixed in 4.2.12\n- symfony/security-http (Packagist): affected from 4.1.0; fixed in 4.2.12\n- symfony/security-http (Packagist): affected from 4.3.0; fixed in 4.3.8\n- symfony/security-http (Packagist): affected from 4.3.0; fixed in 4.3.8\n- symfony/symfony (Packagist): affected from 4.1.0; fixed in 4.2.12\n- symfony/symfony (Packagist): affected from 4.1.0; fixed in 4.2.12\n- symfony/symfony (Packagist): affected from 4.3.0; fixed in 4.3.8\n- symfony/symfony (Packagist): affected from 4.3.0; fixed in 4.3.8\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-2019-18886/ (Markdown: https://insights.sbomify.com/CVE-2019-18886/index.md)","id":"CVE-2019-18886","markdown":"https://insights.sbomify.com/CVE-2019-18886/index.md","name":"CVE-2019-18886","record":{"aliases":["DEBIAN-CVE-2019-18886","GHSA-4vpc-5jx4-cfqg"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["data_read"],"network_reachable":"yes","non_default_config":false,"product_category":"Symfony security component","requires_auth":"none","summary":"Attackers can enumerate valid users by observing differences in response handling during unauthorized user switching attempts in the Symfony security component.","user_interaction":"not_required","vuln_class":"information_disclosure"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"mitre","cpe":[{"product":"symfony","vendor":"sensiolabs"}],"cvss":{"score":5.3,"severity":"medium","source":"nvd","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"}],"description":"An issue was discovered in Symfony 4.2.0 to 4.2.11 and 4.3.0 to 4.3.7. The ability to enumerate users was possible due to different handling depending on whether the user existed when making unauthorized attempts to use the switch users functionality. This is related to symfony/security.","ecosystems":["Packagist"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"User enumeration leak using switch user functionality in Symfony","id":"CVE-2019-18886","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Packagist","product":"sensiolabs:symfony","products":["sensiolabs:symfony"],"type":"information_disclosure","year":"2019"},"n_packages":8,"n_references":3,"next":{"headline":"Symfony Http-Kernel has non-constant time comparison in UriSigner","id":"CVE-2019-18887"},"packages":[{"ecosystem":"Packagist","fixed":["4.2.12"],"introduced":["4.1.0"],"last_affected":[],"package":"symfony/security-http","purl":null,"source":"GHSA-4vpc-5jx4-cfqg"},{"ecosystem":"Packagist","fixed":["4.2.12"],"introduced":["4.1.0"],"last_affected":[],"package":"symfony/security-http","purl":"pkg:composer/symfony/security-http","source":"GHSA-4vpc-5jx4-cfqg"},{"ecosystem":"Packagist","fixed":["4.3.8"],"introduced":["4.3.0"],"last_affected":[],"package":"symfony/security-http","purl":null,"source":"GHSA-4vpc-5jx4-cfqg"},{"ecosystem":"Packagist","fixed":["4.3.8"],"introduced":["4.3.0"],"last_affected":[],"package":"symfony/security-http","purl":"pkg:composer/symfony/security-http","source":"GHSA-4vpc-5jx4-cfqg"},{"ecosystem":"Packagist","fixed":["4.2.12"],"introduced":["4.1.0"],"last_affected":[],"package":"symfony/symfony","purl":null,"source":"GHSA-4vpc-5jx4-cfqg"},{"ecosystem":"Packagist","fixed":["4.2.12"],"introduced":["4.1.0"],"last_affected":[],"package":"symfony/symfony","purl":"pkg:composer/symfony/symfony","source":"GHSA-4vpc-5jx4-cfqg"},{"ecosystem":"Packagist","fixed":["4.3.8"],"introduced":["4.3.0"],"last_affected":[],"package":"symfony/symfony","purl":null,"source":"GHSA-4vpc-5jx4-cfqg"},{"ecosystem":"Packagist","fixed":["4.3.8"],"introduced":["4.3.0"],"last_affected":[],"package":"symfony/symfony","purl":"pkg:composer/symfony/symfony","source":"GHSA-4vpc-5jx4-cfqg"}],"prev":{"headline":"Null dereference in n/a","id":"CVE-2019-18885"},"products":["n/a"],"published":"2019-11-21","related":[{"cvss_score":9.8,"headline":"Improper Input Validation in Symfony","id":"CVE-2019-11325","kev_date_added":null,"published":"2019-11-21"},{"cvss_score":9.8,"headline":"Symfony Incorrect Access Control","id":"CVE-2017-11365","kev_date_added":null,"published":"2019-05-23"},{"cvss_score":9.8,"headline":"Invalid HTTP method overrides allow possible XSS or other attacks in Symfony","id":"CVE-2019-10913","kev_date_added":null,"published":"2019-05-16"},{"cvss_score":9.8,"headline":"Symfony Authentication Bypass","id":"CVE-2018-11407","kev_date_added":null,"published":"2018-06-13"},{"cvss_score":9.8,"headline":"Symfony Authentication Bypass","id":"CVE-2016-2403","kev_date_added":null,"published":"2017-02-07"},{"cvss_score":9.1,"headline":"Symfony: Identity Spoofing via Unanchored DN Regex in X509Authenticator","id":"CVE-2026-45063","kev_date_added":null,"published":"2026-07-14"},{"cvss_score":8.8,"headline":"Symfony: OidcTokenHandler Accepts JWTs Missing aud/iss/exp Claims","id":"CVE-2026-45069","kev_date_added":null,"published":"2026-07-14"}],"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)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2024-08-05","vendors":["n/a"]},"summary":"Attackers can enumerate valid users by observing differences in response handling during unauthorized user switching attempts in the Symfony security component.","url":"https://insights.sbomify.com/CVE-2019-18886/"}