CVE-2025-34523: arcserve udp Heap-based Buffer Overflow

Vulnerability summary

CVE-2025-34523 is a critical (CVSS 9.8) Heap-based Buffer Overflow vulnerability in arcserve udp. EPSS estimates a 0.53% chance of exploitation in the next 30 days, higher than 43.7% of scored vulnerabilities.

Timeline

1. 27-08-2025
   PublishedVulnerability first disclosed.
2. 04-08-2026
   Last modifiedVulnerability information updated.

Description

A heap-based buffer overflow vulnerability exists in the network-facing input handling routines of Arcserve Unified Data Protection (UDP). This flaw is reachable without authentication and results from improper bounds checking when processing attacker-controlled input. By sending specially crafted data, a remote attacker can corrupt heap memory, potentially causing a denial of service or enabling arbitrary code execution depending on the memory layout and exploitation techniques used. This vulnerability is similar in nature to CVE-2025-34522 but affects a separate code path or component. No user interaction is required, and exploitation occurs in the context of the vulnerable process. 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.

• CWE-122Heap-based Buffer OverflowA heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().