{"answers":{"affected":"5 open source packages ship an affected version, including ash_authentication.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-49757 exists.","fix":"Upgrade ash_authentication to a fixed version for your release line: 4.14.0 or 5.0.0-rc.10.","what":"CVE-2026-49757 is a critical authentication bypass vulnerability in team-alembic ash_authentication, published on 15 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-49757 and fix it if it is affected.\n\nWhat it is: CVE-2026-49757 is a critical authentication bypass vulnerability in team-alembic ash_authentication, published on 15 Jun 2026. 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-2026-49757 exists.\n\nAffected packages and fixed versions:\n- ash_authentication (Hex): affected from 0.1.0; fixed in 4.14.0, 5.0.0-rc.10\n- ash_authentication (Hex): affected from 0.1.0; fixed in 4.14.0\n- ash_authentication (Hex): affected from 0.1.0; fixed in 4.14.0\n- ash_authentication (Hex): affected from 5.0.0-rc.0; fixed in 5.0.0-rc.10\n- ash_authentication (Hex): affected from 5.0.0-rc.0; fixed in 5.0.0-rc.10\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-2026-49757/ (Markdown: https://insights.sbomify.com/CVE-2026-49757/index.md)","id":"CVE-2026-49757","markdown":"https://insights.sbomify.com/CVE-2026-49757/index.md","name":"CVE-2026-49757","record":{"aliases":["CVE-2026-55616","EEF-CVE-2026-49757","GHSA-777c-2fxx-qr28"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["account_takeover","privilege_escalation"],"network_reachable":"yes","non_default_config":false,"product_category":"Elixir authentication library","requires_auth":"none","summary":"Attackers can take over local user accounts by registering with a victim's email on an OAuth provider, bypassing proper identity verification.","user_interaction":"not_required","vuln_class":"auth_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"EEF","cpe":[],"cvss":{"score":9.2,"severity":"critical","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","version":"4.0"},"cwes":[{"id":"CWE-290","name":"Authentication Bypass by Spoofing"}],"description":"Authentication Bypass by Spoofing vulnerability in team-alembic AshAuthentication allows account takeover of local users via OAuth2/OIDC sign-in.\n\nAshAuthentication's OAuth2 and OIDC family strategies matched the local user by email address (an upsert on the email field, or a user-defined sign-in filter) rather than by the OpenID Connect iss/sub claim combination. Per OpenID Connect Core §5.7, only iss/sub uniquely and stably identifies an end-user; other claims, including email, MUST NOT be used as unique identifiers.\n\nA provider login presenting a victim's email, including an unverified email, a reused email, or an account with email_verified: false, resolved to and signed in as the victim's existing local account. An unauthenticated attacker who can register an account on any accepted OAuth provider with the victim's email (or who benefits from provider-side email reuse or reclamation) obtains the victim's full local privileges.\n\nThe fix resolves users by the (strategy, sub) identity stored in a user identity resource, and only links a new sub to an existing local account by email when the provider's email_verified claim is trusted (trust_email_verified?).\n\nThis issue affects ash_authentication from 0.1.0 before 4.14.0 and from 5.0.0-rc.0 before 5.0.0-rc.10.","ecosystems":["Hex"],"exploits":{"exploitdb":0,"first_seen":"2026-06-21","github_poc":1,"max_poc_stars":0,"metasploit":0,"nuclei":0,"refs":[{"date":"2026-06-21T07:03:58Z","kind":"github_poc","ref":"https://github.com/Hunt-Benito/ash-authentication-oauth2-oidc-account-takeover-cve-2026-49757-email-based-user-matching","stars":0,"title":null}],"tier":"weaponised"},"has_fix":true,"headline":"OAuth2/OIDC account takeover in AshAuthentication via email-based user matching","id":"CVE-2026-49757","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Hex","product":null,"products":[],"type":"auth_bypass","year":"2026"},"n_packages":5,"n_references":5,"next":{"headline":"Stack buffer overflow in SCTP error cause parsing in inet_drv allows remote VM crash","id":"CVE-2026-49759"},"packages":[{"ecosystem":"Hex","fixed":["4.14.0","5.0.0-rc.10"],"introduced":["0.1.0","5.0.0-rc.0"],"last_affected":[],"package":"ash_authentication","purl":"pkg:hex/ash_authentication","source":"EEF-CVE-2026-49757"},{"ecosystem":"Hex","fixed":["4.14.0"],"introduced":["0.1.0"],"last_affected":[],"package":"ash_authentication","purl":null,"source":"GHSA-777c-2fxx-qr28"},{"ecosystem":"Hex","fixed":["4.14.0"],"introduced":["0.1.0"],"last_affected":[],"package":"ash_authentication","purl":"pkg:hex/ash_authentication","source":"GHSA-777c-2fxx-qr28"},{"ecosystem":"Hex","fixed":["5.0.0-rc.10"],"introduced":["5.0.0-rc.0"],"last_affected":[],"package":"ash_authentication","purl":null,"source":"GHSA-777c-2fxx-qr28"},{"ecosystem":"Hex","fixed":["5.0.0-rc.10"],"introduced":["5.0.0-rc.0"],"last_affected":[],"package":"ash_authentication","purl":"pkg:hex/ash_authentication","source":"GHSA-777c-2fxx-qr28"}],"prev":{"headline":"Multipart form-data header injection in Req via unescaped name/filename/content_type","id":"CVE-2026-49756"},"products":["ash_authentication"],"published":"2026-06-15","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"Erlang Ecosystem Foundation","prefix":"EEF"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"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":"yes","exploitation":"poc","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-06-15","vendors":["team-alembic"]},"summary":"Attackers can take over local user accounts by registering with a victim's email on an OAuth provider, bypassing proper identity verification.","url":"https://insights.sbomify.com/CVE-2026-49757/"}