by Kastro
Paper/Archive/CVE-2026-15617

CVE-2026-15617

Logto Logto — Principal/domain lookup without case normalization

EPSS 0.4%CVSS 9.1
critical.is priorityof 100
35
CVSS 9.1 (ADP)9.1 / 10 × 3027.3Not in CISA KEV+300.0EPSS percentile 37.0.370 × 207.4No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

Logto performs principal lookup without normalizing email and identifier strings, enabling principal collision and unauthorized account access via case- or Unicode-different identities.

Affected

ProductAffectedFixed inSource
Logto1.10.1 – 1.37.1–CNA

Scores by source

CISA ADP9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: partial

References

refgithub.com/logto-io/logto/blob/ea3ede35028dfd0bbb6d7b239623ce0e7f6cdff8/packages/core/src/libraries/verification-helpers/single-sign-on-guard.ts#L23-L33