Arcserve UDP < 10.2 Authentication Bypass

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.

Timeline

Scores

EPSS (exploitation in 30 days)

0.37% · top 69% of all CVEs (7 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: no · Technical impact: total

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.7.

Weakness

• CWE-288 Authentication Bypass Using an Alternate Path or Channel (opens in a new tab)All about CWE-288 and its CVEs

Affected products

• Arcserve · Unified Data Protection (UDP)

  • unaffected 10.2
  • affected 8.0 – ≤ 10.1
  • affected ≤ 7.*

References (1)

• https://support.arcserve.com/s/article/Important-Security-Bulletin-Must-read-for-all-Arcserve-UDP-customers-on-all-versions (opens in a new tab)vendor-advisorypatch

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2025-34520](https://trackcve.app/badge/CVE-2025-34520.svg)](https://trackcve.app/cve/CVE-2025-34520)

Record last updated 15 May 2026, 11:15 UTC.