CVE-2025-55123 in Adserver
Summary
by MITRE • 11/20/2025
Improper neutralization of input in Revive Adserver 5.5.2 and 6.0.1 and earlier versions causes manager accounts to be able to craft XSS attacks to their own advertiser users.
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Analysis
by VulDB Data Team • 12/05/2025
The vulnerability identified as CVE-2025-55123 represents a critical cross-site scripting flaw within Revive Adserver versions 5.5.2 and 6.0.1 and earlier releases. This weakness stems from inadequate input validation and sanitization mechanisms that fail to properly neutralize malicious user-supplied data before processing. The vulnerability specifically affects manager accounts who possess administrative privileges within the advertising platform, enabling them to exploit this weakness to craft targeted XSS attacks against advertiser users. The flaw exists at the input processing layer where user-entered content is not adequately filtered or escaped before being stored or rendered within the application's user interface. This improper neutralization creates a persistent security gap that allows attackers to inject malicious scripts into the application's response, which then executes in the context of the victim's browser when they interact with the compromised content.
The technical exploitation of this vulnerability follows a pattern that aligns with CWE-79 Cross-site Scripting attacks, specifically targeting the application's failure to properly sanitize user inputs. Attackers with manager privileges can leverage this weakness to inject malicious JavaScript code through various input fields within the adserver interface. The impact is particularly concerning as it enables privilege escalation and lateral movement within the advertising platform's user management system. When advertiser users interact with compromised content, the injected scripts execute in their browser context, potentially leading to session hijacking, credential theft, or unauthorized modifications to advertising campaigns. The vulnerability's exploitation requires minimal user interaction beyond the normal operation of the adserver interface, making it particularly dangerous in environments where manager accounts have broad access to advertiser user data and campaign management features.
The operational impact of CVE-2025-55123 extends beyond simple script execution to encompass potential data compromise and service disruption within advertising platforms. Manager accounts that can craft XSS attacks against advertiser users represent a significant threat vector as these administrators typically possess elevated privileges and access to sensitive advertising data. The vulnerability enables attackers to potentially steal advertising campaign credentials, modify ad delivery settings, or exfiltrate sensitive user information from the advertising platform. This weakness can be exploited to create persistent backdoors within the advertising ecosystem, allowing attackers to maintain access to advertiser accounts over extended periods. The attack surface is further expanded due to the nature of advertising platforms where multiple users interact with shared systems, potentially enabling cascading effects where a single compromised manager account can affect numerous advertiser users.
Organizations utilizing Revive Adserver versions 5.5.2 and 6.0.1 should prioritize immediate remediation through official security patches provided by the vendor. The mitigation strategy must include comprehensive input validation and output encoding mechanisms to prevent the injection of malicious scripts into application responses. Network segmentation and privilege separation can help reduce the impact of potential exploitation by limiting the scope of access that compromised manager accounts can achieve. Security monitoring should focus on identifying anomalous user behavior patterns that might indicate exploitation attempts, particularly around campaign modification activities and user account access patterns. The vulnerability's classification under ATT&CK framework as a web application vulnerability with potential for credential access and privilege escalation requires organizations to implement layered security controls including web application firewalls, regular security assessments, and user behavior analytics to detect and prevent exploitation attempts. Additionally, security awareness training for administrator users should emphasize the importance of input validation and the risks associated with crafting malicious payloads within administrative interfaces.