CVE-2026-101403 in Siebel Apps
Summary
by MITRE • 10/21/2026
Vulnerability in the Siebel Apps - Marketing product of Oracle Siebel CRM (component: Email Marketing). 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 Apps - Marketing. Successful attacks require human interaction from a person other than the attacker. Successful attacks of this vulnerability can result in unauthorized access to critical data or complete access to all Siebel Apps - Marketing accessible data as well as unauthorized update, insert or delete access to some of Siebel Apps - Marketing accessible data. CVSS 3.1 Base Score 5.9 (Confidentiality and Integrity impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/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 Email Marketing component of Oracle Siebel CRM, specifically affecting supported versions ranging from 17.0 through 26.9. This security flaw is classified as a complex attack vector that requires specific conditions to be successfully exploited by an unauthenticated attacker. The primary characteristic of this weakness is its reliance on social engineering or user interaction, meaning the vulnerability cannot be triggered automatically via automated scripts without human involvement. An attacker must leverage network access over HTTP to target the Siebel Apps - Marketing interface, exploiting a design flaw that allows for unauthorized data manipulation when a victim interacts with maliciously crafted content.
From a technical perspective, this vulnerability aligns closely with CWE-79, which describes Cross-Site Scripting (XSS) or similar injection flaws where user input is not properly sanitized before being processed by the application. The requirement for human interaction indicates that the attack likely involves tricking an authenticated administrator or marketing specialist into clicking a malicious link or opening a compromised email within the Siebel environment. Once this interaction occurs, the attacker can execute arbitrary commands or access sensitive data structures that are normally protected from unauthenticated users. This bypasses standard authentication mechanisms by exploiting the trust relationship between the user's session and the application server during specific marketing-related operations.
The operational impact of a successful exploitation is significant for organizations relying on Oracle Siebel CRM for their customer relationship management and email campaigns. The CVSS 3.1 base score of 5.9 reflects moderate severity, driven primarily by high impacts on confidentiality and integrity while availability remains unaffected. Successful attacks enable unauthorized access to critical business data, including potentially sensitive customer information stored within the marketing modules. Furthermore, attackers gain the ability to perform unauthorized updates, inserts, or deletes against accessible Siebel Apps - Marketing data. This compromise of integrity can lead to corrupted campaign metrics, altered contact lists, or the insertion of malicious content into outgoing communications, thereby damaging organizational reputation and operational continuity.
In terms of industry standard mapping, this vulnerability exhibits characteristics consistent with ATT&CK technique T1059, Command and Scripting Interpreter, if script execution is involved, or more broadly falls under Initial Access techniques such as T1566, Phishing, due to the human interaction requirement. The lack of authentication required for initial access combined with the need for user action places this in a category often seen in web application vulnerabilities where session management or input validation logic fails to distinguish between legitimate and malicious requests effectively after the initial trust boundary is crossed via social engineering.
Mitigation strategies must focus on both technical controls and procedural changes. Oracle has likely released patches addressing this specific flaw within the Email Marketing component; therefore, immediate patching of all affected Siebel CRM versions from 17.0 to 26.9 is the primary remediation step. Organizations should also implement strict input validation and output encoding mechanisms for any web-facing components that handle user-generated content. Additionally, deploying Web Application Firewalls (WAF) with rulesets tuned to detect common injection patterns can provide an additional layer of defense. Security awareness training is crucial in this context, as the vulnerability's exploitation depends on human interaction; educating staff about phishing tactics and suspicious links within marketing platforms significantly reduces the attack surface. Regular security assessments and penetration testing should be conducted to identify similar logic flaws before they are exploited by adversaries.