CVE-2026-55789

HIGH
MEDIUM Priority: 0.03 BB Relevance: 67/100
Published: 2026-07-10 Modified: 2026-10-25 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Interaction Integ. Impact Scope Change

CVSS Vector Breakdown

AV: Network
AC: Low
PR: Low
UI: None
S: Changed
C: Low
I: High
A: None

Description

Logto is the modern, open-source auth infrastructure for SaaS and AI apps. Prior to 1.41.0, Logto's self-hosted SAML application IdP built the signed SAML response and assertion by string-substituting user-controlled profile attributes such as name, email, and custom attribute-mapping values into element-text placeholders of a SAML XML template using samlify 2.10.0, which left those placeholders unescaped. An authenticated low-privilege user could place XML markup in a profile attribute so Logto signed a forged SAML attribute, such as an arbitrary role, allowing privilege escalation at relying Service Providers that authorize on SAML attributes. This issue is fixed in version 1.41.0.

Weakness Classification (1)

Bug Bounty Relevance

67 / 100
✓ Network accessible
✓ Low complexity
✓ No user interaction

CVSS Score

8.5 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:N

EPSS — Exploitation Probability

0.34%
Raw Score 0.003440
Percentile 27.9%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00344
2026-10-28
0.00344

Intelligence Sources

nvd ref →