CVE-2025-52869: QNAP Systems Qsync Central · Buffer Overflow
Affects QNAP Systems Qsync CentralSource CVE Database V5
Not known to be exploited · CVSS 0.6 Low : upgrade to 5.0.0.4 ( 2026/01/20 ) when convenient.
Data as of 26 Oct 2026, 14:05 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.
- Patch
- Available – fixed in 5.0.0.4 ( 2026/01/20 )
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:UExploitation evidence
Disclosed: evidence found.
CVE published 11 Feb 2026
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
Upgrade QNAP Systems Qsync Central to 5.0.0.4 ( 2026/01/20 ).
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| QNAP Systems Inc.Qsync Central | Affected
| Fixed in
|
AI-suggested
European organizations should immediately verify their Qsync Central version and upgrade to version 5.0.0.4 or later to remediate the vulnerability. Beyond patching, organizations should enforce strict access controls and monitor user account activities to detect unauthorized access attempts. Implement multi-factor authentication (MFA) to reduce the risk of credential compromise. Network segmentation can limit exposure of Qsync Central services to trusted internal networks. Employ intrusion detection systems (IDS) and anomaly detection to identify unusual process crashes or memory corruption patterns indicative of exploitation attempts. Regularly audit logs for signs of exploitation or suspicious behavior. Additionally, maintain up-to-date backups of synchronized data to ensure recovery capability in case of service disruption. Educate users about credential security to minimize insider threat risks. Finally, coordinate with QNAP support for any additional security advisories or patches.
Description
CVE-2025-52869 is a buffer overflow vulnerability in QNAP Systems Inc. 's Qsync Central software, specifically affecting version 5.0.x.x. A remote attacker with a valid user account can exploit this flaw to modify memory or crash processes, potentially disrupting service or causing instability. The vulnerability does not require user interaction but does require low-level privileges (a user account). The issue has been fixed in Qsync Central version 5.0.0.