CVE-2025-34521
MediumCVSS 5.4Exploitation Probability (EPSS)
Low risk11th percentile - higher than 11% of all known CVEs
Summary
A reflected cross-site scripting (XSS) vulnerability exists in the web interface of Arcserve Unified Data Protection (UDP), where unsanitized user input is improperly reflected in HTTP responses. Remote attackers with low privileges can craft malicious links that, when visited by another user, execute arbitrary JavaScript in the victim's browser. Successful exploitation may lead to session hijacking, credential theft, or other client-side impacts. The vulnerability affects all UDP versions prior to 10.2; versions 8.0 through 10.1 require patch or upgrade to 10.2; versions 7.x and earlier must be upgraded to 10.2.
Risk Assessment
Risk includes session hijacking, credential theft, and other client-side attacks, potentially compromising user and organizational security.
Recommendation
Upgrade Arcserve UDP to version 10.2 or apply appropriate patches for versions 8.0-10.1; versions 7.x and earlier must be upgraded to 10.2.
Other vulnerabilities in Arcserve Unified Data Protection
See all- CVE-2025-34523Critical
A heap-based buffer overflow vulnerability exists in the network-facing input handling routines of Arcserve Unified Data Protection (UDP). It is reachable without authentication and results from improper bounds checking when processing attacker-controlled input.
- CVE-2025-34522Critical
A heap-based buffer overflow vulnerability exists in the input parsing logic of Arcserve Unified Data Protection (UDP). It can be triggered without authentication by sending specially crafted input, potentially leading to application crashes or remote code execution.
- CVE-2025-34520Critical
An authentication bypass vulnerability in Arcserve Unified Data Protection (UDP) allows unauthenticated attackers to gain unauthorized access to protected functionality or user accounts. By manipulating request parameters or exploiting a logic flaw, an attacker can bypass login mechanisms and access administrator-level features. This affects all UDP versions prior to 10.2.
Original NVD description (English source)
A reflected cross-site scripting (XSS) vulnerability exists in the web interface of the Arcserve Unified Data Protection (UDP), where unsanitized user input is improperly reflected in HTTP responses. This flaw allows remote attackers with low privileges to craft malicious links that, when visited by another user, execute arbitrary JavaScript in the victim’s browser. Successful exploitation may lead to session hijacking, credential theft, or other client-side impacts. The vulnerability requires user interaction and occurs within a shared browser context. This vulnerability affects all UDP versions prior to 10.2. UDP 10.2 includes the necessary patches and requires no action. Versions 8.0 through 10.1 are supported and require either patch application or upgrade to 10.2. Versions 7.x and earlier are unsupported or out of maintenance and must be upgraded to 10.2 to remediate the issue.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

