4.8
MEDIUM CVSS 4.0
CVE-2025-34521
Arcserve Unified Data Protection (UDP) Reflected Cross-Site Scripting (XSS) Vulnerability
Description

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.

INFO

Published Date :

Aug. 27, 2025, 10:15 p.m.

Last Modified :

Aug. 29, 2025, 4:24 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2025-34521 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 MEDIUM [email protected]
Solution
Update Arcserve UDP to version 10.2 to fix the reflected cross-site scripting vulnerability.
  • Upgrade to Arcserve UDP version 10.2.
  • Apply patches if using versions 8.0 through 10.1.
  • Upgrade unsupported versions 7.x and earlier to 10.2.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2025-34521.

URL Resource
https://support.arcserve.com/s/article/Important-Security-Bulletin-Must-read-for-all-Arcserve-UDP-customers-on-all-versions
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2025-34521 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2025-34521 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2025-34521 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2025-34521 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Aug. 27, 2025

    Action Type Old Value New Value
    Added Description 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.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-79
    Added Reference https://support.arcserve.com/s/article/Important-Security-Bulletin-Must-read-for-all-Arcserve-UDP-customers-on-all-versions
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 4.8
Attack Vector
Attack Complexity
Attack Requirements
Privileges Required
User Interaction
VS Confidentiality
VS Integrity
VS Availability
SS Confidentiality
SS Integrity
SS Availability