8.5
HIGH CVSS 3.1
CVE-2026-55789
Logto: SAML IdP injects user-controlled profile attributes raw into signed assertions, allowing privilege escalation at relying Service Providers
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.

INFO

Published Date :

July 10, 2026, 8:16 p.m.

Last Modified :

July 10, 2026, 8:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-55789 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 SAML attribute injection.
  • Update Logto to version 1.41.0 or later.
  • Review and sanitize user-provided SAML attributes.
  • Implement proper XML escaping for attribute values.
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-2026-55789 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-2026-55789 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-2026-55789 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-55789 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]

    Jul. 10, 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 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.
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:N
    Added CWE CWE-91
    Added Reference https://github.com/logto-io/logto/commit/9097054860f0d638d90778d3dcde2ba050b844b6
    Added Reference https://github.com/logto-io/logto/pull/9107
    Added Reference https://github.com/logto-io/logto/releases/tag/v1.41.0
    Added Reference https://github.com/logto-io/logto/security/advisories/GHSA-vfpw-vq44-4p63
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.