Vulnerability details
CVE-2026-62317
Logto: ReDoS via unescaped user input in email subaddressing regex (blockSubaddressing)
Official 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.
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 7.5High | 3.1 | CVEProject cvelistV5 (CNA) (GitHub_M) | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| logto-io | logto | < 1.41.0 | CVEProject cvelistV5 (CNA) |
References and advisories
4- https://github.com/logto-io/logto/pull/9106 x_refsource_MISC
- https://github.com/logto-io/logto/commit/021381237511bc0d42f81d65df8b036b01f40547 x_refsource_MISC
- https://github.com/logto-io/logto/releases/tag/v1.41.0 x_refsource_MISC
- https://github.com/logto-io/logto/security/advisories/GHSA-qp7j-c3q2-g739 x_refsource_CONFIRM
Details
- Published
- 2026-08-19
- Last updated
- 2026-08-21
- State
- Published
- Assigner (CNA)
- GitHub_M
Exploit prediction (EPSS)
SSVC assessment (CISA)
- Automatable
- Yes
- Exploitation
- Proof of concept
- Technical impact
- Partial
Weaknesses (CWE)
- CWE-1333Inefficient Regular Expression Complexity