CVE-2025-12765: pgAdmin 4 Auth Bypass Vulnerability

CVE-2025-12765 Overview

CVE-2025-12765 affects pgAdmin versions 9.9 and earlier. The vulnerability resides in the Lightweight Directory Access Protocol (LDAP) authentication mechanism, which fails to properly verify TLS certificates during the authentication flow. Attackers positioned on the network path between pgAdmin and the LDAP server can intercept authentication traffic without triggering certificate validation errors. This weakness is categorized under CWE-295: Improper Certificate Validation. Successful exploitation enables credential theft and authentication impersonation against PostgreSQL administrative interfaces.

Critical Impact

Attackers can intercept LDAP authentication traffic to capture pgAdmin user credentials and impersonate authenticated sessions, leading to unauthorized access to PostgreSQL database management functions.

Affected Products

• pgAdmin 4 versions up to and including 9.9
• Deployments using LDAP authentication backend
• pgAdmin instances configured with TLS-protected LDAP connections

Discovery Timeline

• 2025-11-13 - CVE-2025-12765 published to NVD
• 2025-11-19 - Last updated in NVD database

Technical Details for CVE-2025-12765

Vulnerability Analysis

The vulnerability stems from improper TLS certificate validation in the pgAdmin LDAP authentication module. When pgAdmin establishes a TLS-protected connection to an LDAP directory server, the client does not enforce verification of the server certificate chain or hostname. This allows any TLS endpoint to terminate the authentication session, regardless of whether its certificate is trusted by the configured certificate authority store.

Attackers exploiting this flaw operate as a man-in-the-middle between pgAdmin and the legitimate LDAP server. The pgAdmin client accepts forged certificates and forwards user credentials to the attacker-controlled endpoint. The attack requires network positioning, which increases exploitation complexity but does not require authentication or user interaction.

This vulnerability is classified as a Certificate Validation Bypass affecting the integrity and confidentiality of the authentication channel. No public proof-of-concept code is available at the time of disclosure.

Root Cause

The pgAdmin LDAP client does not configure the underlying LDAP library to require certificate validation. Trust verification flags such as TLS_REQCERT are either not set to demand or are overridden during connection setup. The client establishes encrypted sessions without confirming the server identity.

Attack Vector

An attacker on the same network segment as a pgAdmin server, or positioned at an intermediate network hop, intercepts the outbound LDAP connection. The attacker presents a self-signed or forged certificate to the pgAdmin client. pgAdmin completes the TLS handshake and transmits user credentials in the LDAP bind request. The attacker captures these credentials and optionally proxies the connection to the real LDAP server to avoid detection.

Refer to the pgAdmin GitHub issue tracker for technical discussion of the flaw.

Detection Methods for CVE-2025-12765

Indicators of Compromise

• Unexpected LDAP authentication failures or anomalous bind patterns in pgAdmin logs
• LDAP traffic terminating at hosts other than the configured directory server
• TLS certificates presented by LDAP endpoints that do not match the organization's certificate authority
• pgAdmin sessions originating from unusual source addresses following LDAP authentication events

Detection Strategies

• Inspect network flows from pgAdmin hosts to confirm LDAP traffic reaches only authorized directory servers
• Compare TLS certificate fingerprints observed on LDAP connections against the expected server certificate
• Audit pgAdmin configuration files for LDAP TLS settings and verify the trusted CA bundle path
• Correlate authentication events between pgAdmin and the LDAP server to identify mismatched bind attempts

Monitoring Recommendations

• Enable verbose logging on pgAdmin authentication modules to capture LDAP bind attempts and TLS negotiation details
• Deploy network detection rules that flag LDAP/LDAPS traffic to unexpected destinations on port 636 or 389
• Monitor for ARP spoofing, DNS poisoning, and rogue DHCP activity on segments hosting pgAdmin instances
• Establish baseline metrics for LDAP authentication latency and alert on deviations consistent with proxied connections

How to Mitigate CVE-2025-12765

Immediate Actions Required

• Upgrade pgAdmin to a version released after 9.9 that addresses the certificate validation flaw
• Restrict network paths between pgAdmin servers and LDAP directory servers using segmentation and firewall rules
• Rotate credentials for any accounts that authenticated to pgAdmin through LDAP during the exposure window
• Review pgAdmin LDAP configuration to enforce strict TLS certificate validation where supported

Patch Information

Monitor the pgAdmin GitHub issue tracker for patch release announcements. Apply the fixed release to all pgAdmin deployments using LDAP authentication. Verify the upgrade in a staging environment before production rollout.

Workarounds

• Disable LDAP authentication temporarily and revert to internal pgAdmin authentication until a patched release is deployed
• Place pgAdmin and the LDAP server on an isolated management network to reduce attacker positioning opportunities
• Pin the LDAP server certificate at the network layer using TLS inspection appliances configured to reject untrusted certificates
• Enforce mutual TLS authentication on the LDAP server where supported to require client certificate presentation

# Configuration example
# Review pgAdmin config_local.py LDAP settings
# Confirm CA certificate path and verification settings after patching
LDAP_USE_STARTTLS = True
LDAP_CA_CERT_FILE = '/etc/pki/tls/certs/ldap-ca.pem'
LDAP_CERT_FILE = ''
LDAP_KEY_FILE = ''