CVE-2026-62317
HighCVSS 7.5Exploitation Probability (EPSS)
Low risk48th percentile - higher than 48% of all known CVEs
Summary
Logto before version 1.41.0 has a catastrophic backtracking vulnerability in the regular expression used for email subaddressing blocking. An attacker can send a specially crafted email address, causing an event-loop stall and making authentication services unavailable.
Risk Assessment
The risk is service disruption, which can prevent login, token issuance, SSO, and access to the administrative console.
Recommendation
Update Logto to version 1.41.0 or later, which includes the fix.
Other vulnerabilities in Logto
See all- CVE-2026-63203High
Logto from 1.31.0 to 1.42.0 has a vulnerability in the Account API handlers in packages/core/src/routes/account/third-party-tokens.ts that allow a caller holding a same-user access token with only the openid scope to retrieve stored social or enterprise SSO provider access tokens through GET /api/my-account/identities/{target}/access-token or GET /api/my-account/sso-identities/{connectorId}/access-token. The handlers authenticate the user but do not require the identities scope that protects neighboring identity-detail operations, bypassing the intended Account API consent boundary.
- CVE-2026-15617Critical
Logto performs principal lookup without normalizing email and identifier strings, enabling principal collision and unauthorized account access via case- or Unicode-different identities.
- CVE-2026-15616Critical
Logto does not enforce locally configured MFA during SSO authentication, allowing users to bypass second-factor requirements and grants unauthorized access.
- CVE-2026-15612Critical
Logto bypasses OIDC nonce validation when the nonce claim is absent from the id_token, enabling replay of authentication tokens and weakening session-binding.
- CVE-2026-15611Critical
Logto allows unverified email-based SSO account linking, enabling an attacker to register an identity at a permissive IdP using a victim’s email and gain unauthorized access to the victim’s account.
- CVE-2026-56739High
Logto before version 1.43.0 fetches administrator-controlled outbound destinations without validating the connection address. Webhook delivery and custom/OIDC connectors can reach special-use and cloud metadata addresses, potentially exposing internal data or upstream provider credentials. This issue is fixed in version 1.43.0.
- CVE-2026-82263Medium
Logto through 1.42.0 contains a server-side request forgery vulnerability in the OIDC SSO connector creation endpoint that fails to validate the issuer URL parameter. Tenant administrators with Management API credentials can supply arbitrary internal URLs to trigger HTTP GET requests to private network services, with response content returned in API responses.
- CVE-2026-82262Medium
Logto through 1.42.0 contains a server-side request forgery vulnerability in the POST /api/hooks/:id/test endpoint that accepts arbitrary URLs without host validation. Tenant administrators with Management API tokens can make the server issue HTTP POST requests to internal URLs and retrieve response bodies from services on the private network.
- CVE-2026-63187Medium
Logto, the modern open-source auth infrastructure, versions 1.40.1 to 1.41.0, has a vulnerability in GitHub Actions workflow where the pull request title is directly interpolated into an echo command in the commitlint step. A title containing a single quote can terminate the echo string and append arbitrary shell commands on the runner. An attacker can disrupt the ephemeral workflow execution, but repository secrets are not exposed.
- CVE-2026-15615High
Logto omits validation of the SAML <Conditions> element, enabling attackers to strip time and audience restrictions and replay assertions indefinitely.
Original NVD description (English source)
Logto is the modern, open-source auth infrastructure for SaaS and AI apps. Prior to 1.41.0, Logto's email subaddressing blocklist in packages/core/src/libraries/sign-in-experience/email-blocklist-policy.ts used the attacker-controlled domain from email input to construct subaddressingRegex when blockSubaddressing was enabled. The permissive emailRegEx accepted multiple at signs and regular expression metacharacters, and POST /api/experience/verification/verification-code could therefore cause catastrophic backtracking in subaddressingRegex.test(email). The resulting event-loop stall could make authentication, token issuance, SSO, and the administrative console unavailable. This issue is fixed in version 1.41.0.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

