{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-49757", "assignerOrgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "state": "PUBLISHED", "assignerShortName": "EEF", "dateReserved": "2026-06-01T13:45:22.449Z", "datePublished": "2026-06-15T10:07:17.781Z", "dateUpdated": "2026-06-15T14:14:37.882Z"}, "containers": {"cna": {"affected": [{"collectionURL": "https://repo.hex.pm", "cpes": ["cpe:2.3:a:team-alembic:ash_authentication:*:*:*:*:*:*:*:*"], "defaultStatus": "unaffected", "modules": ["'Elixir.AshAuthentication.Strategy.OAuth2.IdentityChange'", "'Elixir.AshAuthentication.Strategy.OAuth2.SignInPreparation'"], "packageName": "ash_authentication", "packageURL": "pkg:hex/ash_authentication", "product": "ash_authentication", "programFiles": ["lib/ash_authentication/strategies/oauth2/identity_change.ex", "lib/ash_authentication/strategies/oauth2/sign_in_preparation.ex"], "programRoutines": [{"name": "'Elixir.AshAuthentication.Strategy.OAuth2.IdentityChange':change/3"}, {"name": "'Elixir.AshAuthentication.Strategy.OAuth2.SignInPreparation':prepare/3"}], "repo": "https://github.com/team-alembic/ash_authentication", "vendor": "team-alembic", "versions": [{"lessThan": "4.14.0", "status": "affected", "version": "0.1.0", "versionType": "semver"}, {"lessThan": "5.0.0-rc.10", "status": "affected", "version": "5.0.0-rc.0", "versionType": "semver"}]}, {"collectionURL": "https://github.com", "cpes": ["cpe:2.3:a:team-alembic:ash_authentication:*:*:*:*:*:*:*:*"], "defaultStatus": "unaffected", "modules": ["'Elixir.AshAuthentication.Strategy.OAuth2.IdentityChange'", "'Elixir.AshAuthentication.Strategy.OAuth2.SignInPreparation'"], "packageName": "team-alembic/ash_authentication", "packageURL": "pkg:github/team-alembic/ash_authentication", "product": "ash_authentication", "programFiles": ["lib/ash_authentication/strategies/oauth2/identity_change.ex", "lib/ash_authentication/strategies/oauth2/sign_in_preparation.ex"], "programRoutines": [{"name": "'Elixir.AshAuthentication.Strategy.OAuth2.IdentityChange':change/3"}, {"name": "'Elixir.AshAuthentication.Strategy.OAuth2.SignInPreparation':prepare/3"}], "repo": "https://github.com/team-alembic/ash_authentication.git", "vendor": "team-alembic", "versions": [{"changes": [{"at": "728b8d28c1b5f465fa1116ef044a815300fc733d", "status": "unaffected"}, {"at": "64530644f9b37ebb76ca14aeb83a77597a0034b7", "status": "unaffected"}], "lessThan": "*", "status": "affected", "version": "c5f589058e04239263f50a1430eb17ea6d5dd1a2", "versionType": "git"}]}], "cpeApplicability": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:team-alembic:ash_authentication:*:*:*:*:*:*:*:*", "versionEndExcluding": "4.14.0", "versionStartIncluding": "0.1.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:team-alembic:ash_authentication:*:*:*:*:*:*:*:*", "versionEndExcluding": "5.0.0-rc.10", "versionStartIncluding": "5.0.0-rc.0", "vulnerable": true}], "negate": false, "operator": "OR"}], "operator": "AND"}], "credits": [{"lang": "en", "type": "finder", "value": "Jarl Andr\u00e9 H\u00fcbenthal"}, {"lang": "en", "type": "remediation developer", "value": "James Harton"}, {"lang": "en", "type": "analyst", "value": "Jonatan M\u00e4nnchen / EEF"}], "descriptions": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "Authentication Bypass by Spoofing vulnerability in team-alembic AshAuthentication allows account takeover of local users via OAuth2/OIDC sign-in.<p>AshAuthentication'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 <tt>iss</tt>/<tt>sub</tt> claim combination. Per OpenID Connect Core \u00a75.7, only <tt>iss</tt>/<tt>sub</tt> uniquely and stably identifies an end-user; other claims, including <tt>email</tt>, MUST NOT be used as unique identifiers.</p><p>A provider login presenting a victim's email, including an unverified email, a reused email, or an account with <tt>email_verified: false</tt>, 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.</p><p>The fix resolves users by the <tt>(strategy, sub)</tt> identity stored in a user identity resource, and only links a new <tt>sub</tt> to an existing local account by email when the provider's <tt>email_verified</tt> claim is trusted (<tt>trust_email_verified?</tt>).</p><p>This 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.</p>"}], "value": "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 \u00a75.7, 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."}], "impacts": [{"capecId": "CAPEC-21", "descriptions": [{"lang": "en", "value": "CAPEC-21 Exploitation of Trusted Identifiers"}]}], "metrics": [{"cvssV4_0": {"attackComplexity": "LOW", "attackRequirements": "PRESENT", "attackVector": "NETWORK", "baseScore": 9.2, "baseSeverity": "CRITICAL", "privilegesRequired": "NONE", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "vectorString": "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", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH"}, "format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "problemTypes": [{"descriptions": [{"cweId": "CWE-290", "description": "CWE-290 Authentication Bypass by Spoofing", "lang": "en", "type": "CWE"}]}], "providerMetadata": {"orgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "shortName": "EEF", "dateUpdated": "2026-06-15T14:14:37.882Z"}, "references": [{"tags": ["vendor-advisory", "related"], "url": "https://github.com/team-alembic/ash_authentication/security/advisories/GHSA-777c-2fxx-qr28"}, {"tags": ["related"], "url": "https://cna.erlef.org/cves/CVE-2026-49757.html"}, {"tags": ["related"], "url": "https://osv.dev/vulnerability/EEF-CVE-2026-49757"}, {"tags": ["patch"], "url": "https://github.com/team-alembic/ash_authentication/commit/728b8d28c1b5f465fa1116ef044a815300fc733d"}, {"tags": ["patch"], "url": "https://github.com/team-alembic/ash_authentication/commit/64530644f9b37ebb76ca14aeb83a77597a0034b7"}], "source": {"discovery": "EXTERNAL"}, "title": "OAuth2/OIDC account takeover in AshAuthentication via email-based user matching", "x_generator": {"engine": "cvelib 1.8.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-06-15T12:35:13.009558Z", "id": "CVE-2026-49757", "options": [{"Exploitation": "poc"}, {"Automatable": "yes"}, {"Technical Impact": "total"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-06-15T12:35:41.459Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-49757", "role": "CISA Coordinator", "options": [{"Exploitation": "poc"}, {"Automatable": "yes"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-06-15T12:35:13.009558Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-06-15T12:35:34.621Z"}}], "cna": {"title": "OAuth2/OIDC account takeover in AshAuthentication via email-based user matching", "source": {"discovery": "EXTERNAL"}, "credits": [{"lang": "en", "type": "finder", "value": "Jarl Andr\u00e9 H\u00fcbenthal"}, {"lang": "en", "type": "remediation developer", "value": "James Harton"}, {"lang": "en", "type": "analyst", "value": "Jonatan M\u00e4nnchen / EEF"}], "impacts": [{"capecId": "CAPEC-21", "descriptions": [{"lang": "en", "value": "CAPEC-21 Exploitation of Trusted Identifiers"}]}], "metrics": [{"format": "CVSS", "cvssV4_0": {"version": "4.0", "baseScore": 9.2, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "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", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "HIGH"}, "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "affected": [{"cpes": ["cpe:2.3:a:team-alembic:ash_authentication:*:*:*:*:*:*:*:*"], "repo": "https://github.com/team-alembic/ash_authentication", "vendor": "team-alembic", "modules": ["'Elixir.AshAuthentication.Strategy.OAuth2.IdentityChange'", "'Elixir.AshAuthentication.Strategy.OAuth2.SignInPreparation'"], "product": "ash_authentication", "versions": [{"status": "affected", "version": "0.1.0", "lessThan": "4.14.0", "versionType": "semver"}, {"status": "affected", "version": "5.0.0-rc.0", "lessThan": "5.0.0-rc.10", "versionType": "semver"}], "packageURL": "pkg:hex/ash_authentication", "packageName": "ash_authentication", "programFiles": ["lib/ash_authentication/strategies/oauth2/identity_change.ex", "lib/ash_authentication/strategies/oauth2/sign_in_preparation.ex"], "collectionURL": "https://repo.hex.pm", "defaultStatus": "unaffected", "programRoutines": [{"name": "'Elixir.AshAuthentication.Strategy.OAuth2.IdentityChange':change/3"}, {"name": "'Elixir.AshAuthentication.Strategy.OAuth2.SignInPreparation':prepare/3"}]}, {"cpes": ["cpe:2.3:a:team-alembic:ash_authentication:*:*:*:*:*:*:*:*"], "repo": "https://github.com/team-alembic/ash_authentication.git", "vendor": "team-alembic", "modules": ["'Elixir.AshAuthentication.Strategy.OAuth2.IdentityChange'", "'Elixir.AshAuthentication.Strategy.OAuth2.SignInPreparation'"], "product": "ash_authentication", "versions": [{"status": "affected", "changes": [{"at": "728b8d28c1b5f465fa1116ef044a815300fc733d", "status": "unaffected"}, {"at": "64530644f9b37ebb76ca14aeb83a77597a0034b7", "status": "unaffected"}], "version": "c5f589058e04239263f50a1430eb17ea6d5dd1a2", "lessThan": "*", "versionType": "git"}], "packageURL": "pkg:github/team-alembic/ash_authentication", "packageName": "team-alembic/ash_authentication", "programFiles": ["lib/ash_authentication/strategies/oauth2/identity_change.ex", "lib/ash_authentication/strategies/oauth2/sign_in_preparation.ex"], "collectionURL": "https://github.com", "defaultStatus": "unaffected", "programRoutines": [{"name": "'Elixir.AshAuthentication.Strategy.OAuth2.IdentityChange':change/3"}, {"name": "'Elixir.AshAuthentication.Strategy.OAuth2.SignInPreparation':prepare/3"}]}], "references": [{"url": "https://github.com/team-alembic/ash_authentication/security/advisories/GHSA-777c-2fxx-qr28", "tags": ["vendor-advisory", "related"]}, {"url": "https://cna.erlef.org/cves/CVE-2026-49757.html", "tags": ["related"]}, {"url": "https://osv.dev/vulnerability/EEF-CVE-2026-49757", "tags": ["related"]}, {"url": "https://github.com/team-alembic/ash_authentication/commit/728b8d28c1b5f465fa1116ef044a815300fc733d", "tags": ["patch"]}, {"url": "https://github.com/team-alembic/ash_authentication/commit/64530644f9b37ebb76ca14aeb83a77597a0034b7", "tags": ["patch"]}], "x_generator": {"engine": "cvelib 1.8.0"}, "descriptions": [{"lang": "en", "value": "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 \u00a75.7, 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.", "supportingMedia": [{"type": "text/html", "value": "Authentication Bypass by Spoofing vulnerability in team-alembic AshAuthentication allows account takeover of local users via OAuth2/OIDC sign-in.<p>AshAuthentication'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 <tt>iss</tt>/<tt>sub</tt> claim combination. Per OpenID Connect Core \u00a75.7, only <tt>iss</tt>/<tt>sub</tt> uniquely and stably identifies an end-user; other claims, including <tt>email</tt>, MUST NOT be used as unique identifiers.</p><p>A provider login presenting a victim's email, including an unverified email, a reused email, or an account with <tt>email_verified: false</tt>, 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.</p><p>The fix resolves users by the <tt>(strategy, sub)</tt> identity stored in a user identity resource, and only links a new <tt>sub</tt> to an existing local account by email when the provider's <tt>email_verified</tt> claim is trusted (<tt>trust_email_verified?</tt>).</p><p>This 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.</p>", "base64": false}]}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-290", "description": "CWE-290 Authentication Bypass by Spoofing"}]}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:team-alembic:ash_authentication:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "4.14.0", "versionStartIncluding": "0.1.0"}, {"criteria": "cpe:2.3:a:team-alembic:ash_authentication:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.0.0-rc.10", "versionStartIncluding": "5.0.0-rc.0"}], "operator": "OR"}], "operator": "AND"}], "providerMetadata": {"orgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "shortName": "EEF", "dateUpdated": "2026-06-15T14:14:37.882Z"}}}, "cveMetadata": {"cveId": "CVE-2026-49757", "state": "PUBLISHED", "dateUpdated": "2026-06-15T14:14:37.882Z", "dateReserved": "2026-06-01T13:45:22.449Z", "assignerOrgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "datePublished": "2026-06-15T10:07:17.781Z", "assignerShortName": "EEF"}, "dataVersion": "5.2"}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "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 \u00a75.7, 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."}], "id": "CVE-2026-49757", "lastModified": "2026-06-15T12:16:25.777", "metrics": {"cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 9.2, "baseSeverity": "CRITICAL", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "version": "4.0", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "type": "Secondary"}]}, "published": "2026-06-15T12:16:25.777", "references": [{"source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "url": "https://cna.erlef.org/cves/CVE-2026-49757.html"}, {"source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "url": "https://github.com/team-alembic/ash_authentication/commit/64530644f9b37ebb76ca14aeb83a77597a0034b7"}, {"source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "url": "https://github.com/team-alembic/ash_authentication/commit/728b8d28c1b5f465fa1116ef044a815300fc733d"}, {"source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "url": "https://github.com/team-alembic/ash_authentication/security/advisories/GHSA-777c-2fxx-qr28"}, {"source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "url": "https://osv.dev/vulnerability/EEF-CVE-2026-49757"}], "sourceIdentifier": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-290"}], "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "type": "Secondary"}]}

{}