CVE-2026-91429 in Siebel CRM Deployment
Summary
by MITRE • 10/21/2026
Vulnerability in the Siebel CRM Deployment product of Oracle Siebel CRM (component: Server Infrastructure). Supported versions that are affected are 17.0-26.9. Difficult to exploit vulnerability allows unauthenticated attacker with network access via HTTP to compromise Siebel CRM Deployment. Successful attacks of this vulnerability can result in unauthorized access to critical data or complete access to all Siebel CRM Deployment accessible data as well as unauthorized update, insert or delete access to some of Siebel CRM Deployment accessible data. CVSS 3.1 Base Score 6.5 (Confidentiality and Integrity impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N).
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Analysis
by VulDB Data Team • 10/21/2026
The identified vulnerability resides within the Server Infrastructure component of Oracle Siebel CRM, specifically affecting deployment versions ranging from 17.0 through 26.9. This security flaw represents a significant risk to organizations relying on this customer relationship management platform for critical business operations. The core issue stems from an architectural weakness in how the server infrastructure handles incoming HTTP requests without properly enforcing authentication mechanisms before processing sensitive data queries or modifications. Because the vulnerability is classified as difficult to exploit, it suggests that while the underlying logic flaw exists and allows unauthorized access, successful exploitation may require specific conditions or precise sequencing of actions that are not trivial for an average attacker to replicate. However, the difficulty level does not negate the severity of the potential impact if those conditions are met by a determined adversary with network connectivity to the affected system.
From a technical perspective, this vulnerability allows unauthenticated attackers who have network access via HTTP to compromise the integrity and confidentiality of the Siebel CRM Deployment environment. The absence of proper authentication checks at critical points in the request handling process enables malicious actors to bypass standard security controls. This lack of authorization verification means that any entity capable of reaching the server over the network can interact with internal APIs or endpoints designed for administrative or data management tasks. Consequently, attackers are not required to possess valid user credentials or session tokens to initiate these unauthorized interactions. The vulnerability essentially exposes sensitive backend operations to external networks without the necessary gatekeeping mechanisms, creating a direct path from an unauthenticated state to privileged actions within the application layer.
The operational impact of this flaw is substantial, primarily affecting data confidentiality and integrity while leaving availability largely unaffected according to the provided CVSS metrics. Successful exploitation can lead to unauthorized access to critical business data stored within the Siebel CRM system. This includes sensitive customer information, sales pipelines, contact details, and other proprietary datasets that are central to organizational operations. Beyond mere observation of this data, the vulnerability also permits unauthorized updates, inserts, or deletes against accessible data sets. This capability allows attackers not only to exfiltrate valuable intelligence but also to corrupt existing records, inject false entries, or remove essential information entirely. Such actions can disrupt business processes, lead to financial loss through fraudulent activities based on manipulated data, and cause significant reputational damage due to compromised customer trust.
In terms of industry-standard classification frameworks, this vulnerability aligns with CWE-287 Improper Authentication, as the system fails to adequately verify identity before granting access to protected resources. It also relates closely to CWE-601 URL Redirection to Untrusted Site or Open Redirect if the exploitation involves manipulating request paths, though the primary issue is the lack of authentication checks on sensitive endpoints. Within the MITRE ATT&CK framework, this behavior corresponds to techniques associated with Initial Access and Credential Access, specifically where attackers leverage exposed services to gain footholds without traditional credential theft. The CVSS 3.1 base score of 6.5 reflects a medium severity rating driven by high confidentiality impact and low integrity impact, with an attack vector that is network-based but requires high complexity for successful exploitation. This scoring indicates that while the vulnerability is serious enough to warrant immediate attention due to its potential data exposure risks, it may not be as easily weaponized in widespread automated attacks compared to lower-complexity flaws.
Mitigation strategies should focus on both immediate remediation and long-term architectural improvements. Organizations running affected versions of Oracle Siebel CRM must apply the latest security patches provided by Oracle as soon as they are available for their specific version line. If patching is not immediately feasible, implementing strict network segmentation to restrict HTTP access from untrusted networks can significantly reduce the attack surface. Additionally, deploying a Web Application Firewall with rules specifically tuned to detect anomalous request patterns associated with this vulnerability type can provide an additional layer of defense by blocking unauthorized attempts before they reach the application server. It is also advisable to enforce multi-factor authentication for all administrative and privileged accounts within the Siebel environment to mitigate risks if other layers are bypassed. Regular security audits and penetration testing should be conducted to identify similar misconfigurations or unauthenticated endpoints across the infrastructure, ensuring a holistic approach to securing customer data against evolving threats.