CVE-2019-14857 in mod_auth_openidc
Summary
by MITRE
mod_auth_openidc before version 2.4.0.1 is vulnerable to a None
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Analysis
by VulDB Data Team • 01/02/2026
The vulnerability identified as CVE-2019-14857 affects mod_auth_openidc versions prior to 2.4.0.1, representing a critical authentication bypass flaw that undermines the security of OpenID Connect authentication implementations. This module serves as an Apache HTTP Server module that enables OpenID Connect authentication for web applications, making it a crucial component in identity management infrastructure. The vulnerability stems from inadequate validation of authentication responses, specifically allowing malicious actors to bypass the authentication process entirely by manipulating the OpenID Connect flow.
The technical flaw manifests in the module's failure to properly validate the authentication state and response parameters during the OpenID Connect authorization flow. This weakness enables attackers to craft specially crafted requests that can trick the authentication module into accepting invalid or unauthorized authentication responses. The vulnerability operates at the protocol level where the module should validate the integrity of the OpenID Connect response, including checking the authentication state parameter, nonce values, and ensuring proper session management. Without these validations, attackers can exploit the module to authenticate as any user, effectively bypassing all access controls.
From an operational perspective, this vulnerability presents a severe risk to organizations relying on mod_auth_openidc for securing their web applications and services. The impact extends beyond simple unauthorized access to potentially enable privilege escalation, data breaches, and lateral movement within networks where these applications are deployed. The vulnerability affects any system running Apache HTTP Server with mod_auth_openidc module installed and configured for OpenID Connect authentication, making it particularly dangerous in enterprise environments where single sign-on and identity federation are common practices. Attackers can exploit this flaw without requiring prior authentication credentials, making it especially dangerous in scenarios where the module is used to protect sensitive corporate or customer data.
The vulnerability aligns with CWE-287 which addresses improper authentication issues, and maps to ATT&CK technique T1078 for valid accounts and T1566 for credential stuffing attacks. Organizations should immediately update to mod_auth_openidc version 2.4.0.1 or later to address this vulnerability. Additional mitigations include implementing network segmentation, monitoring authentication logs for unusual patterns, and ensuring proper configuration of the module's security parameters. Security teams should also conduct thorough vulnerability assessments to identify any systems running affected versions and implement comprehensive monitoring solutions to detect potential exploitation attempts. The fix addresses the core validation issues by implementing proper state parameter checking and ensuring that authentication responses are verified against expected values before granting access.