CVE-2026-54714 json
Logto: XSS via unescaped RelayState in SAML auto-submit form
published 4mo ago modified 17d ago also EUVD-2026-43009
- cvss
- 6.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 27%
- public exploits
- 0
- none known
Summary
Logto is the modern, open-source auth infrastructure for SaaS and AI apps. Prior to 1.41.0, @logto/core reflected the SAML RelayState, SAMLResponse, and actionUrl into a Logto-origin auto-submit HTML form in packages/core/src/saml-application/SamlApplication/utils.ts without HTML-attribute escaping. A SAML application flow with a crafted RelayState from GET or POST /api/saml/:id/authn could inject script that runs on the Logto tenant origin after the user completes login. This issue is fixed in version 1.41.0.
Patch / fix
- github.com/logto-io/logto@209fa0a commit
- github.com/logto-io/logto#9008 pull request
- github.com/logto-io/logto/releases/tag/v1.41.0 release
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 3mo ago
Exploit prediction
0.34% chance of exploitation in the next 30 days, higher than 27% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
Affected products
- logto-io logto
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
Sources
- CVE List CVE-2026-54714
- NVD CVE-2026-54714
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