{"answers":{"affected":"1 open source package ship an affected version, including ash_authentication.","exploited":"There is no known exploitation of CVE-2026-82761 in the wild and no public exploit code.","fix":"Upgrade ash_authentication to a fixed version for your release line: 4.15.0 or 5.0.0-rc.14.","what":"CVE-2026-82761 is a critical vulnerability in team-alembic ash_authentication, published on 17 Sep 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-2026-82761 and fix it if it is affected.\n\nWhat it is: CVE-2026-82761 is a critical vulnerability in team-alembic ash_authentication, published on 17 Sep 2026. 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-2026-82761 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- ash_authentication (Hex): affected from 3.9.0; fixed in 4.15.0, 5.0.0-rc.14\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-2026-82761/ (Markdown: https://insights.sbomify.com/CVE-2026-82761/index.md)","id":"CVE-2026-82761","markdown":"https://insights.sbomify.com/CVE-2026-82761/index.md","name":"CVE-2026-82761","record":{"aliases":["EEF-CVE-2026-82761","GHSA-23gr-vcp4-r27q"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["account_takeover"],"network_reachable":"yes","non_default_config":false,"product_category":"Elixir authentication library","requires_auth":"none","summary":"Attackers can replay leaked magic link tokens to authenticate as victims due to a race condition in token revocation logic.","user_interaction":"not_required","vuln_class":"race_condition"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"EEF","cpe":[],"cvss":{"score":9.1,"severity":"critical","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","version":"4.0"},"cwes":[{"id":"CWE-367","name":"Time-of-check Time-of-use (TOCTOU) Race Condition"}],"description":"Time-of-check Time-of-use (TOCTOU) Race Condition vulnerability in team-alembic AshAuthentication allows an attacker holding a leaked magic link to replay its single-use token and authenticate as the target subject. A magic link configured with single_use_token?, which is the default, is meant to be redeemable exactly once, but nothing serialises the token's validity check against its consumption, so concurrent redemptions of one token all succeed and each yields a full user token.\n\nSign-in verifies the JWT with Jwt.verify/4 and revokes it only afterwards: AshAuthentication.Strategy.MagicLink.SignInPreparation revokes in a Query.after_action callback, and AshAuthentication.Strategy.MagicLink.SignInChange in an after_transaction hook that runs once the sign-in has already committed. AshAuthentication.TokenResource.Actions.revoke/3 writes the revocation as an upsert, so a concurrent duplicate revocation silently succeeds instead of conflicting and no request ever loses the race.\n\nThis issue affects ash_authentication: from 3.9.0 before 4.15.0 and from 5.0.0-rc.0 before 5.0.0-rc.14.","ecosystems":["Hex"],"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":"Magic link single-use tokens replayable via TOCTOU race in AshAuthentication","id":"CVE-2026-82761","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Hex","product":null,"products":[],"type":"race_condition","year":"2026"},"n_packages":1,"n_references":6,"next":{"headline":"Command injection in FXA3000","id":"CVE-2026-82762"},"packages":[{"ecosystem":"Hex","fixed":["4.15.0","5.0.0-rc.14"],"introduced":["3.9.0","5.0.0-rc.0"],"last_affected":[],"package":"ash_authentication","purl":"pkg:hex/ash_authentication","source":"EEF-CVE-2026-82761"}],"prev":{"headline":"Superlinear base62 decoding exhausts CPU and memory in AshAuthentication API key sign-in","id":"CVE-2026-82760"},"products":["ash_authentication"],"published":"2026-09-17","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":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"yes","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-09-17","vendors":["team-alembic"]},"summary":"Attackers can replay leaked magic link tokens to authenticate as victims due to a race condition in token revocation logic.","url":"https://insights.sbomify.com/CVE-2026-82761/"}