---
id: CVE-2026-74241
title: 'Quay: ldap referral filter injection in quay external ldap authentication'
summary: >-
  A flaw was found in Red Hat Quay's external Lightweight Directory Access
  Protocol (LDAP) authentication handling. When an LDAP referral is returned
  during authentication, the system does not properly escape the username input.
  This allow…
severity: medium
cvss: 4.8
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N'
cvssSource: cna
cwe:
  - CWE-90
vendor: Red Hat
product: openshift-update-service/openshift-update-service-rhel8
affected:
  - openshift-update-service/openshift-update-service-rhel8 (all versions)
  - quay/quay-rhel8 (all versions)
  - quay/quay-rhel9 (all versions)
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-08-17T15:51:44.176289Z'
published: '2026-08-14'
updated: '2026-11-01'
sourceUpdated: '2026-11-01T05:03:02.124Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-74241'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2026-74241'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2516141'
    label: RHBZ#2516141
tags:
  - cve.org
epss: 0.0031
epssPercentile: 0.23969
ingestedAt: '2026-11-05T18:28:50.682Z'
---

## Overview

A flaw was found in Red Hat Quay's external Lightweight Directory Access Protocol (LDAP) authentication handling. When an LDAP referral is returned during authentication, the system does not properly escape the username input. This allows an attacker to inject LDAP filter metacharacters, enabling user-existence oracle attacks at the referral Directory Name (DN). This could also potentially influence which DN is used for password binding in multi-domain Active Directory environments.

## Affected

- `openshift-update-service/openshift-update-service-rhel8 (all versions)`
- `quay/quay-rhel8 (all versions)`
- `quay/quay-rhel9 (all versions)`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

### Workarounds

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.