CVE-2026-62317: CWE-1333: Inefficient Regular Expression Complexity in logto-io logto
CVE-2026-62317 is a high-severity vulnerability in logto-io's Logto authentication infrastructure prior to version 1.41.0. It involves inefficient regular expression complexity in the email subaddressing blocklist logic, which can cause catastrophic backtracking and stall the event loop. This denial-of-service condition affects authentication, token issuance, SSO, and the administrative console availability. The issue is fixed in version 1.41.0.
AI Analysis
Technical Summary
Logto versions before 1.41.0 contain a vulnerability where the email subaddressing blocklist uses an attacker-controlled domain from email input to build a regular expression (subaddressingRegex) when blockSubaddressing is enabled. The emailRegEx used is permissive, accepting multiple '@' signs and regex metacharacters, enabling crafted input to trigger catastrophic backtracking in subaddressingRegex.test(email). This leads to an event-loop stall causing denial of service for authentication-related endpoints including POST /api/experience/verification/verification-code. The vulnerability is identified as CWE-1333 (Inefficient Regular Expression Complexity) and has a CVSS 3.1 score of 7.5 (high severity).
Potential Impact
Exploitation of this vulnerability results in denial of service by stalling the event loop, making critical authentication functions such as token issuance, single sign-on, and administrative console access unavailable. There is no impact on confidentiality or integrity reported. No known exploits are currently in the wild.
Mitigation Recommendations
This vulnerability is fixed in Logto version 1.41.0. Users should upgrade to version 1.41.0 or later to remediate the issue. No additional mitigation is required once the upgrade is applied.
CVE-2026-62317: CWE-1333: Inefficient Regular Expression Complexity in logto-io logto
Description
CVE-2026-62317 is a high-severity vulnerability in logto-io's Logto authentication infrastructure prior to version 1.41.0. It involves inefficient regular expression complexity in the email subaddressing blocklist logic, which can cause catastrophic backtracking and stall the event loop. This denial-of-service condition affects authentication, token issuance, SSO, and the administrative console availability. The issue is fixed in version 1.41.0.
CVSS v3.1
Score 7.5high
Affected software
logto-io
logto
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Logto versions before 1.41.0 contain a vulnerability where the email subaddressing blocklist uses an attacker-controlled domain from email input to build a regular expression (subaddressingRegex) when blockSubaddressing is enabled. The emailRegEx used is permissive, accepting multiple '@' signs and regex metacharacters, enabling crafted input to trigger catastrophic backtracking in subaddressingRegex.test(email). This leads to an event-loop stall causing denial of service for authentication-related endpoints including POST /api/experience/verification/verification-code. The vulnerability is identified as CWE-1333 (Inefficient Regular Expression Complexity) and has a CVSS 3.1 score of 7.5 (high severity).
Potential Impact
Exploitation of this vulnerability results in denial of service by stalling the event loop, making critical authentication functions such as token issuance, single sign-on, and administrative console access unavailable. There is no impact on confidentiality or integrity reported. No known exploits are currently in the wild.
Mitigation Recommendations
This vulnerability is fixed in Logto version 1.41.0. Users should upgrade to version 1.41.0 or later to remediate the issue. No additional mitigation is required once the upgrade is applied.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-07-13T19:27:58.314Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6a860996acd9273b498b4c93
Added to database: 08/19/2026, 19:52:54 UTC
Last enriched: 09/11/2026, 05:32:12 UTC
Last updated: 10/02/2026, 09:10:09 UTC
Views: 75
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