{"answers":{"affected":"2 open source packages ship an affected version, including @backstage/plugin-auth-backend-module-cloudflare-access-provider. It affects 2 products.","exploited":"There is no known exploitation of CVE-2026-106457 in the wild and no public exploit code.","fix":"Upgrade @backstage/plugin-auth-backend-module-cloudflare-access-provider to 0.5.0 or later.","what":"CVE-2026-106457 is a medium-severity authentication bypass vulnerability in Linuxfoundation Backstage, published on 6 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-106457 and fix it if it is affected.\n\nWhat it is: CVE-2026-106457 is a medium-severity authentication bypass vulnerability in Linuxfoundation Backstage, published on 6 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-106457 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- @backstage/plugin-auth-backend-module-cloudflare-access-provider (npm): affected from 0.1.0; fixed in 0.5.0\n- @backstage/plugin-auth-backend-module-cloudflare-access-provider (npm): affected from 0.1.0; fixed in 0.5.0\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-2026-106457/ (Markdown: https://insights.sbomify.com/CVE-2026-106457/index.md)","id":"CVE-2026-106457","markdown":"https://insights.sbomify.com/CVE-2026-106457/index.md","name":"CVE-2026-106457","record":{"aliases":["GHSA-q333-f498-w2x7"],"analysis":{"component_type":"web_application","fix_type":"upgrade","impacts":["account_takeover"],"network_reachable":"yes","non_default_config":true,"product_category":"Backstage developer portal","requires_auth":"low_privilege","summary":"Attackers with valid tokens for other Cloudflare Access apps can authenticate to Backstage if audience validation is not enforced upstream.","user_interaction":"not_required","vuln_class":"auth_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"backstage","vendor":"linuxfoundation"},{"product":"backstage\\/plugin-auth-backend-module-cloudflare-access-provider","vendor":"linuxfoundation"}],"cvss":{"score":6.8,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N","version":"3.1"},"cwes":[{"id":"CWE-287","name":"Improper Authentication"}],"description":"Backstage is an open framework for building developer portals. From 0.1.0 until 0.5.0, the @backstage/plugin-auth-backend-module-cloudflare-access-provider package is affected by insufficient audience validation in the cloudflare access auth provider. The Cloudflare Access auth provider verifies a token's signature and team issuer, but affected versions do not verify that the token was issued for the Backstage application. A user holding a valid token for another Access application in the same Cloudflare Zero Trust team may therefore be able to authenticate to Backstage if that token reaches the auth endpoint without the Backstage application's audience already being enforced upstream. Cloudflare Access normally evaluates the protected application before forwarding requests. This issue is fixed in version 0.5.0.","ecosystems":["npm"],"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":"Backstage: Insufficient audience validation in the Cloudflare Access auth provider","id":"CVE-2026-106457","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"npm","product":"linuxfoundation:backstage","products":["linuxfoundation:backstage"],"type":"auth_bypass","year":"2026"},"n_packages":2,"n_references":3,"next":{"headline":"Backstage: Inconsistent repository filtering in Bitbucket Server catalog event updates","id":"CVE-2026-106458"},"packages":[{"ecosystem":"npm","fixed":["0.5.0"],"introduced":["0.1.0"],"last_affected":[],"package":"@backstage/plugin-auth-backend-module-cloudflare-access-provider","purl":null,"source":"GHSA-q333-f498-w2x7"},{"ecosystem":"npm","fixed":["0.5.0"],"introduced":["0.1.0"],"last_affected":[],"package":"@backstage/plugin-auth-backend-module-cloudflare-access-provider","purl":"pkg:npm/%40backstage/plugin-auth-backend-module-cloudflare-access-provider","source":"GHSA-q333-f498-w2x7"}],"prev":{"headline":"Backstage: Inconsistent credential enforcement for overlapping proxy routes","id":"CVE-2026-106456"},"products":["backstage","plugin-auth-backend-module-cloudflare-access-provider"],"published":"2026-10-06","related":[{"cvss_score":9.6,"headline":"Backstage: Sensitive information exposure in Scaffolder","id":"CVE-2026-106501","kev_date_added":null,"published":"2026-10-06"},{"cvss_score":8.8,"headline":"Backstage: Improper validation of TechDocs MkDocs configuration","id":"CVE-2026-106558","kev_date_added":null,"published":"2026-10-07"},{"cvss_score":8.8,"headline":"Backstage: Improper input validation in TechDocs MkDocs configuration","id":"CVE-2026-88064","kev_date_added":null,"published":"2026-09-16"},{"cvss_score":8.5,"headline":"Backstage: Improper input validation in Sentry scaffolder actions","id":"CVE-2026-106459","kev_date_added":null,"published":"2026-10-06"},{"cvss_score":8.5,"headline":"Backstage: Improper filesystem validation in Bitbucket pull-request scaffolder actions","id":"CVE-2026-106486","kev_date_added":null,"published":"2026-10-06"},{"cvss_score":8.5,"headline":"Backstage: Improper task state validation in Scaffolder backend","id":"CVE-2026-106500","kev_date_added":null,"published":"2026-10-06"},{"cvss_score":8.5,"headline":"Path Traversal in @backstage/plugin-scaffolder-backend","id":"CVE-2021-43783","kev_date_added":null,"published":"2021-11-29"}],"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":"no","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-10-07","vendors":["@backstage","backstage"]},"summary":"Attackers with valid tokens for other Cloudflare Access apps can authenticate to Backstage if audience validation is not enforced upstream.","url":"https://insights.sbomify.com/CVE-2026-106457/"}