---
id: "CVE-2026-58256"
kind: "vulnerability"
aliases: ["CVE-2026-58256"]
title: "GRR reservation app: admin LDAP settings let attackers run PHP code"
severity: "critical"
cvss: 9.1
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["grr", "ldap", "package", "php", "self-hosted"]
not_affected_if: ["fixed-version", "no-ldap-connector"]
published_at: "2026-10-27T23:17:06+00:00"
first_seen_at: "2026-10-27T23:29:44+00:00"
updated_at: "2026-10-27T23:31:15+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-58256", "first_seen_at": "2026-10-27T23:29:44+00:00"}]
---

# GRR reservation app: admin LDAP settings let attackers run PHP code

GRR, a resource reservation application, writes LDAP connector settings such as ldap_filter into a PHP config file without sanitizing them. An administrator can inject PHP that the server then executes, giving remote code execution on the host.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed GRR version in its release metadata or repository tag; versions before `4.5.0` are listed as affected.
- Look at `/personnalisation/config_ldap.inc.php` for PHP code inside LDAP filter or other connector values that you did not write.

## Fix

- Upgrade GRR to `4.5.0` or later, per the advisory.
- Review LDAP connector settings and the `config_ldap.inc.php` file for injected code, and rotate any credentials the server could read if it was tampered with.

## Timeline

- 2026-10-27T23:29:44+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-58256

## From the sources

GRR is a resource management and reservation application. Prior to the advisory-reported fixed version 4.5.0, an administrator can inject malicious PHP through LDAP connector configuration parameters such as `ldap_filter`, poisoning `/personnalisation/config_ldap.inc.php` and permitting remote code execution. The administrator must first successfully connect to an LDAP server, which can be attacker-controlled, and then submit malicious input on the subsequent connector settings page. The advisory reports this issue as fixed in version 4.5.0.

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