CVE-2025-34522 — Arcserve UDP < 10.2 Pre-Authentication Heap Overflow

A heap-based buffer overflow vulnerability exists in the input parsing logic of Arcserve Unified Data Protection (UDP). This flaw can be triggered without authentication by sending specially crafted input to the target system. Improper bounds checking allows an attacker to overwrite heap memory, potentially leading to application crashes or remote code execution. Exploitation occurs in the context of the affected process and does not require user interaction. The vulnerability poses a high risk due to its pre-authentication nature and potential for full compromise. 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…

Published Aug 27, 2025Updated May 15, 2026Sources: cvelistV5, VulnCheck

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.

Exploitation

Unreported

no source claims exploitation

EPSS

chance of exploitation in 30 days

Affects

arcserve

unified_data_protection_udp

CVSS base

9.2

CRITICAL

CISA SSVC assessment

Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.

CISA

Exploitation

None

none · proof-of-concept · active

Automatable

can an attacker script all four kill-chain steps

Technical impact

Total

partial · total control of the vulnerable component

Affected scope

The catalog records vendors and products as separate lists, not pairs, so which product belongs to which vendor is not something this page can say.

Vendors (1)

arcserve

Products (1)

unified data protection udp

Every base score collected

Sources score independently and disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Source
9.2	CVSS 4.0	CRITICAL	—	—	cvelistV5

Weakness & attack patterns

CWE-122

References

1 on the record

support.arcserve.com/s/article/Important-Security-Bulletin-Must-read-for-all-Arcserve-UDP-customers-on-all-versions
vendor-advisory, patch

Elsewhere on this site

arcserveevery CVE for this vendor
CWE-122other pages naming this weakness

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.