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VulnerabilityPublished

CVE-2025-30269: QNAP Systems Qsync Central · CWE-134

Affects QNAP Systems Qsync CentralSource CVE Database V5

0

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

CVSS 4.0 base score
0.6Low
How severe the flaw is on the 0–10 CVSS scale.
EPSS
0.3% chance of exploitation in 30 days – higher than 25% 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:U

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 11 Feb 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponised: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq 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

ProductAffectedFixed in
QNAP Systems Inc.Qsync CentralAffected
  • =5.0.x.x
Fixed in
  • 5.0.0.4 ( 2026/01/20 )

AI-suggested

European organizations should immediately upgrade Qsync Central installations to version 5.0.0.4 or later, where the vulnerability is patched. In addition to patching, organizations should enforce strong user authentication policies, including multi-factor authentication (MFA), to reduce the risk of credential compromise. Regularly audit user accounts and permissions to ensure that only authorized personnel have access to Qsync Central. Implement network segmentation and access controls to limit exposure of Qsync Central services to trusted networks and users. Monitor logs for unusual activity indicative of exploitation attempts, such as unexpected format string errors or memory anomalies. Educate users on phishing and credential security to prevent account takeover. Finally, consider deploying application-layer firewalls or intrusion detection systems capable of detecting anomalous input patterns consistent with format string exploitation attempts.

Description

CVE-2025-30269 is a use of externally-controlled format string vulnerability in QNAP Systems Inc. 's Qsync Central product. A remote attacker with a valid user account can exploit this flaw to read secret data or modify memory, potentially leading to unauthorized information disclosure or application instability. The vulnerability affects Qsync Central versions 5.0.x.x prior to 5.0.0.4, which was patched in January 2026.

References

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