CVE-2025-34520

Description

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 specific request parameters or exploiting a logic flaw, an attacker can bypass login mechanisms without valid credentials and access administrator-level features. 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.

CVSS v3.1 Score

9.8

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-288 CWE-288

Affected Products

Vendor	Product	Versions
arcserve	udp	< 7.0
arcserve	udp	8.0 — 10.2
arcserve	udp	All
arcserve	udp	All
arcserve	udp	All

References

Advisories & Patches

https://support.arcserve.com/s/article/Important-Security-Bulletin-Must-read-for-all-Arcserve-UDP-customers-on-all-versions

Frequently Asked Questions

What is CVE-2025-34520? +

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 specific request parameters or exploiting a logic flaw, an attacker can bypass login mechanisms without valid credentials and access administrator-level features. 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. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2025-34520? +

CVE-2025-34520 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2025-34520? +

CVE-2025-34520 affects products from arcserve, specifically: udp. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-34520? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-40582

ChurchCRM is an open-source church management system. In versions prior to 7.2.0, the /api/public/user/login endpoint validates only the username and …

CVE-2025-23217

mitmproxy is a interactive TLS-capable intercepting HTTP proxy for penetration testers and software developers and mitmweb is a web-based interface …

CVE-2025-2080

Optigo Networks Visual BACnet Capture Tool and Optigo Visual Networks Capture Tool version 3.1.2rc11 contain an exposed web management service …

CVE-2025-29996

This vulnerability exists in the CAP back office application due to improper implementation of OTP verification mechanism in its API …

CVE-2025-2492

An improper authentication control vulnerability exists in AiCloud. This vulnerability can be triggered by a crafted request, potentially leading to …

CVE-2025-4687

In Teltonika Networks Remote Management System (RMS), it is possible to perform account pre-hijacking by misusing the invite functionality. If …