CVE-2025-30261: QNAP Systems Qsync Central · Unthrottled Resource Allocation
Affects QNAP Systems Qsync CentralSource CVE Database V5
Not known to be exploited · CVSS 7.1 High.
Data as of 26 Oct 2026, 11:42 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 39% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 29 Aug 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
AI-suggested
European organizations should prioritize upgrading Qsync Central to version 5.0.0.0 or later as released by QNAP on June 13, 2025. Beyond patching, organizations should implement strict access controls and monitoring to detect unusual resource consumption patterns indicative of exploitation attempts. Enforcing strong authentication mechanisms, such as multi-factor authentication (MFA), can reduce the risk of unauthorized account access. Network segmentation and limiting Qsync Central access to trusted networks can further reduce exposure. Additionally, resource usage limits or quotas should be configured where possible to prevent any single user from exhausting system resources. Regular auditing of user accounts and prompt revocation of unused or suspicious accounts will also help mitigate risk. Finally, organizations should maintain up-to-date incident response plans to quickly address potential denial of service incidents stemming from this vulnerability.
Description
An allocation of resources without limits or throttling vulnerability has been reported to affect Qsync Central. If a remote attacker gains a user account, they can then exploit the vulnerability to prevent other systems, applications, or processes from accessing the same type of resource. We have already fixed the vulnerability in the following version: Qsync Central 5.0.0.0 ( 2025/06/13 ) and later