Independent & educational platform Not a government body. No link or affiliation with any government organisation. Made for learning only. Test only systems you own or are authorised to test. Become a Partner or Sponsor → Full disclaimer

CVE-2025-34520

critical

An authentication bypass vulnerability in Arcserve Unified Data Protection (UDP) allows unauthenticated attackers to gain unauthorized access to protected func…

Vendor / product: Arcserve — udp

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
9.8
9.8 (CVSS v3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity source: NVD CVSS v3.1 (nvd@nist.gov)
Timeline (UTC)
Published: 2025-08-27 22:15
Modified: 2026-09-26 00:10
NVD status: Analyzed
Last synced 2 days ago
Verified against the source API 2026-10-27 07:06 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

arcserve / udp <7.0, ≥8.0 <10.2, 7.0

Weakness classification (CWE)

CWE-288

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

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

References

Data sources

NVD CVE API 2.0 — fetched 2026-10-27 07:06 UTC · record ↗

Learn the basics

Understanding CVEs and CVSS Scores

Related CVEs

CVE-2025-34522CVE-2025-34523