CVE-2012-3462 in sssd
Summary
by MITRE
A flaw was found in SSSD version 1.9.0. The SSSD's access-provider logic causes the result of the HBAC rule processing to be ignored in the event that the access-provider is also handling the setup of the user's SELinux user context.
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Analysis
by VulDB Data Team • 03/17/2024
The vulnerability described in CVE-2012-3462 resides within the System Security Services Daemon SSSD version 1.9.0, specifically within its access-provider component that manages user authentication and authorization processes. This flaw represents a critical security weakness that undermines the integrity of access control mechanisms by allowing unauthorized access to systems through improper handling of HBAC (Host-Based Access Control) rules. The SSSD serves as a crucial component in enterprise environments, providing centralized identity management and authentication services that bridge traditional identity providers with local system security policies.
The technical root cause of this vulnerability lies in the flawed logic of the access-provider module where HBAC rule processing results are being disregarded when the same component is simultaneously responsible for setting up user SELinux user contexts. This dual responsibility creates a condition where the access control decisions made during HBAC rule evaluation are effectively nullified, allowing users to bypass access restrictions that should have been enforced. The flaw manifests when the system attempts to establish a user's security context while simultaneously processing access control rules, causing the system to ignore the outcome of the HBAC evaluation process. This represents a classic case of improper privilege management and access control enforcement, aligning with CWE-284 which addresses inadequate access control mechanisms.
The operational impact of this vulnerability is severe as it allows attackers to gain unauthorized access to systems by exploiting the broken access control chain. When a user authenticates through SSSD, the system should enforce HBAC rules to determine what resources the user can access, but due to this flaw, those rules are effectively ignored. This creates a scenario where users may gain access to systems or resources that they should not be permitted to access, potentially leading to privilege escalation, data breaches, or unauthorized system modifications. The vulnerability is particularly dangerous in environments where SELinux policies are strictly enforced and HBAC rules are used to implement fine-grained access controls, as it completely undermines the security posture established by these mechanisms.
Organizations using SSSD version 1.9.0 are advised to immediately upgrade to a patched version that resolves this access control flaw. The mitigation strategy should include implementing additional monitoring and logging of access control decisions to detect potential exploitation attempts. Security administrators should also review and validate existing HBAC rules to ensure that access controls are functioning as intended. From an ATT&CK framework perspective, this vulnerability maps to privilege escalation techniques and access control bypass methods, specifically targeting the T1068 privilege escalation tactic and T1078 legitimate credentials sub-technique. Organizations should also consider implementing network segmentation and additional authentication controls as compensating measures while awaiting the official patch deployment. The vulnerability demonstrates the importance of proper separation of duties in security systems and highlights the critical need for thorough testing of access control logic in complex identity management solutions.