What is CVE-2025-34520?

CVE-2025-34520 is a critical-severity vulnerability in Arcserve Udp, classified under Authentication Bypass Using an Alternate Path or Channel. CVSS score: 9.8/10. Published 2025-08-27.

How severe is CVE-2025-34520?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Vulnerability in Arcserve Udp

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 explo…

EPSS: 0.003 (26.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Arcserve Udp — versions 7.0
Arcserve Unified Data Protection (Udp) — versions 10.2, 8.0, 0

Weakness classification (CWE)

CWE-288 — Authentication Bypass Using an Alternate Path or Channel

References

disclosure@vulncheck.com (vendor-advisory, patch, Vendor Advisory)

Frequently asked questions

What is CVE-2025-34520?: CVE-2025-34520 is a critical-severity vulnerability in Arcserve Udp, classified under Authentication Bypass Using an Alternate Path or Channel. CVSS score: 9.8/10. Published 2025-08-27.
How severe is CVE-2025-34520?: Critical severity. CVSS v3 base score is 9.8 out of 10.