7.5
HIGH CVSS 3.1
CVE-2026-62317
Logto: ReDoS via unescaped user input in email subaddressing regex (blockSubaddressing)
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.

INFO

Published Date :

Aug. 19, 2026, 8:17 p.m.

Last Modified :

Aug. 19, 2026, 8:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-62317 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
Solution
Update Logto to version 1.41.0 or later to fix denial-of-service vulnerability.
  • Update Logto to version 1.41.0 or later.
  • Review email validation logic for regex vulnerabilities.
  • Ensure robust input sanitization for email fields.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-62317 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-62317 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-62317 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-62317 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Aug. 19, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'logto-io', 'product': 'logto', 'versions': [{'status': 'affected', 'version': '< 1.41.0'}]}]
    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.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-1333
    Added Reference https://github.com/logto-io/logto/commit/021381237511bc0d42f81d65df8b036b01f40547
    Added Reference https://github.com/logto-io/logto/pull/9106
    Added Reference https://github.com/logto-io/logto/releases/tag/v1.41.0
    Added Reference https://github.com/logto-io/logto/security/advisories/GHSA-qp7j-c3q2-g739
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.