---
id: CVE-2026-53658
title: Fabric CA is a Certificate Authority for Hyperledger Fabric
summary: >-
  Fabric CA is a Certificate Authority for Hyperledger Fabric. Prior to 1.5.21,
  when fabric-ca is configured with an LDAP backend, Client.GetUser in
  lib/server/ldap/client.go inserts the username from HTTP Basic authentication
  into the LDA…
severity: medium
cvss: 6.3
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N'
cwe:
  - CWE-90
vendor: hyperledger
product: fabric-ca
affected:
  - fabric-ca < 1.5.21
patched:
  - github.com/hyperledger/fabric-ca 1.5.21
published: '2026-09-15'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T16:17:08.380'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-53658'
references:
  - url: >-
      https://github.com/hyperledger/fabric-ca/commit/d379df823534d56dec0166a6da8f0415e3beee24
    label: security-advisories@github.com
  - url: 'https://github.com/hyperledger/fabric-ca/pull/501'
    label: security-advisories@github.com
  - url: 'https://github.com/hyperledger/fabric-ca/releases/tag/v1.5.21'
    label: security-advisories@github.com
  - url: >-
      https://github.com/hyperledger/fabric-ca/security/advisories/GHSA-xghw-p77p-3r7x
    label: security-advisories@github.com
  - url: 'https://github.com/advisories/GHSA-xghw-p77p-3r7x'
tags:
  - nvd
  - cve.org
  - ghsa
  - go
aliases:
  - GHSA-xghw-p77p-3r7x
ecosystem: go
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-16T15:37:09.855418Z'
cvssSource: cna
ingestedAt: '2026-08-14T20:20:21.563Z'
epss: 0.0045
epssPercentile: 0.36384
---

## Overview

Fabric CA is a Certificate Authority for Hyperledger Fabric. Prior to 1.5.21, when fabric-ca is configured with an LDAP backend, Client.GetUser in lib/server/ldap/client.go inserts the username from HTTP Basic authentication into the LDAP uid search UserFilter without escaping LDAP metacharacters. An unauthenticated attacker with network access to the CA enrollment endpoint can alter the LDAP search before password validation and potentially steer authentication attempts toward a victim account. Deployments that do not use an LDAP backend are unaffected. This issue is fixed in version 1.5.21.

## Remediation

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

## Package advisory (CVE-2026-53658)

Affected packages:

- `github.com/hyperledger/fabric-ca <= 1.5.20`

Patched in:

- `github.com/hyperledger/fabric-ca 1.5.21`

Source: https://github.com/advisories/GHSA-xghw-p77p-3r7x