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.

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Wed, 19 Aug 2026 21:30:00 +0000

Type Values Removed Values Added
First Time appeared Logto-io
Logto-io logto
Vendors & Products Logto-io
Logto-io logto

Wed, 19 Aug 2026 19:45:00 +0000

Type Values Removed Values Added
Description 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.
Title Logto: ReDoS via unescaped user input in email subaddressing regex (blockSubaddressing)
Weaknesses CWE-1333
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}


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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-08-19T19:41:23.800Z

Reserved: 2026-07-13T19:27:58.314Z

Link: CVE-2026-62317

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-19T20:17:19.890

Modified: 2026-08-19T20:17:19.890

Link: CVE-2026-62317

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-19T21:15:08Z

Weaknesses