CVE-2026-33289: SuiteCRM LDAP Auth Bypass Vulnerability

CVE-2026-33289 Overview

CVE-2026-33289 is an LDAP Injection vulnerability in SuiteCRM, an open-source Customer Relationship Management (CRM) application. The flaw exists in the authentication flow, where the application fails to sanitize user-supplied input before embedding it into the Lightweight Directory Access Protocol (LDAP) search filter. An unauthenticated attacker can inject LDAP control characters to manipulate query logic, leading to authentication bypass or information disclosure. The issue affects all versions prior to 7.15.1 and 8.9.3.

Critical Impact

Unauthenticated network attackers can bypass authentication and access sensitive directory information through crafted LDAP filter injection in the SuiteCRM login flow.

Affected Products

• SuiteCRM versions prior to 7.15.1 (7.x branch)
• SuiteCRM versions prior to 8.9.3 (8.x branch)
• Deployments configured to use LDAP authentication

Discovery Timeline

• 2026-03-20 - CVE-2026-33289 published to NVD
• 2026-03-23 - Last updated in NVD database

Technical Details for CVE-2026-33289

Vulnerability Analysis

The vulnerability resides in the SuiteCRM authentication module that handles LDAP-based logins. The application accepts username input from the login form and concatenates it directly into an LDAP search filter without escaping reserved metacharacters. This allows attackers to alter the structure of the LDAP query rather than merely supplying a value.

LDAP filter syntax uses characters such as *, (, ), \, and \0 as control elements. When unsanitized input containing these characters reaches the directory server, the resulting query can match unintended objects or return broader result sets than intended. The classification falls under [CWE-90] — Improper Neutralization of Special Elements used in an LDAP Query.

Root Cause

The root cause is missing input neutralization on the authentication code path. SuiteCRM constructs LDAP search filters by string concatenation rather than parameterized filter construction or character escaping. The patched releases (7.15.1 and 8.9.3) introduce proper escaping of LDAP metacharacters before query assembly.

Attack Vector

The attack vector is network-based and requires no authentication or user interaction. An attacker submits a crafted username to the SuiteCRM login endpoint. By injecting an LDAP wildcard such as *)(uid=* or a conditional construct, the attacker manipulates the resulting filter to match arbitrary directory entries. Depending on the application's downstream logic, this can authenticate the attacker as an existing user or expose attributes of directory objects through error responses or differential application behavior.

No verified public proof-of-concept is currently available. Refer to the GitHub Security Advisory GHSA-26vx-rj47-x599 for upstream technical details.

Detection Methods for CVE-2026-33289

Indicators of Compromise

• Authentication requests to SuiteCRM login endpoints containing LDAP metacharacters such as *, (, ), or \ in the username field.
• Successful authentications without a corresponding valid user credential pair in application logs.
• Anomalous LDAP query patterns on the directory server showing wildcard or boolean-injected filters originating from the SuiteCRM service account.

Detection Strategies

• Inspect web access logs and application logs for login POST requests where username parameters contain unescaped LDAP control characters.
• Correlate SuiteCRM authentication events with directory server query logs to identify filters that deviate from the expected (uid=<value>) shape.
• Alert on repeated failed-then-successful authentication sequences from a single source IP targeting the login endpoint.

Monitoring Recommendations

• Enable verbose LDAP query logging on the backing directory server during the remediation window.
• Forward SuiteCRM application and web server logs to a centralized analytics platform for retroactive review.
• Track outbound LDAP traffic volume from SuiteCRM hosts; injection probes often produce result sets larger than normal login traffic.

How to Mitigate CVE-2026-33289

Immediate Actions Required

• Upgrade SuiteCRM to version 7.15.1 or 8.9.3 as soon as possible.
• Audit LDAP authentication logs for the past 90 days for filter manipulation patterns.
• Rotate credentials for any administrative accounts that authenticated through SuiteCRM during the exposure window.
• Restrict network access to the SuiteCRM login interface to trusted networks until patching completes.

Patch Information

SuiteCRM addressed the vulnerability in versions 7.15.1 and 8.9.3. Patch details and download links are available in the SuiteCRM Release Notes and the GitHub Security Advisory GHSA-26vx-rj47-x599.

Workarounds

• Disable LDAP authentication and fall back to local database authentication until patches are applied.
• Deploy a web application firewall (WAF) rule that rejects login requests containing LDAP metacharacters in the username parameter.
• Restrict the SuiteCRM service account on the directory server to the minimum search base and attribute set required for authentication.

# Example WAF rule (ModSecurity) blocking LDAP metacharacters in username field
SecRule ARGS:username "@rx [\*\(\)\\\\\\x00]" \
    "id:1026332890,phase:2,deny,status:403,\
    msg:'Possible LDAP injection attempt against SuiteCRM login'"