Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
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AccessObtain valid Qsync Central user account
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ExploitSend crafted request to service
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ExecutionTrigger NULL pointer dereference (CWE-476)
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ImpactCrash service and deny sync access
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A10:2025 - Mishandling of Exceptional Conditions
ASVS 5.0
V16 - Security Logging and Error Handling Null pointer safety, defensive checks
MITRE ATT&CK
1 technique across 1 tactic: Impact The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Exploitation Conditions | Exploitation requires the attacker to first gain a valid Qsync Central user account (PR:L) - the description explicitly states 'If a remote attacker gains a user account.' No user interaction and no special non-default configuration are indicated; the flaw appears reachable over the network against a running Qsync Central instance once authenticated. The key limiting factors are the mandatory authenticated user account and the impact ceiling: the only consequence is a denial of service against the Qsync Central service (availability), with no confidentiality or integrity effect, so a successful attack degrades sync availability rather than compromising data. |
| Impact | This is a genuinely low-priority issue despite a moderate CVSS, and the signals are consistent rather than conflicting. The vendor CVSS 4.0 vector (AV:N/AC:L/PR:L/UI:N) with impact limited to VA:L (low availability, no confidentiality or integrity impact) correctly reflects a CWE-476 NULL pointer dereference that only causes denial of service. The PR:L requirement means the attacker must already hold a valid user account, which meaningfully narrows the exploit population to insiders or attackers who have already obtained credentials. EPSS is low at 0.15% (35th percentile), the CVE is NOT on CISA KEV, and no public exploit was identified in the provided data - all three exploitation signals agree that this is not under active or imminent mass exploitation. No SSVC decision data was supplied. The worst realistic outcome is a service crash/DoS of the Qsync Central component, not code execution or data loss. Net: a real but low-urgency bug best handled through routine patching rather than emergency response. |
| Exploit ScenarioDerived | An attacker who has already obtained a low-privileged Qsync Central user account sends a crafted request that triggers a NULL pointer dereference in the service, crashing it and denying file-sync functionality to legitimate users. No public exploit code was identified, and the attack requires valid authentication, so the practical scenario is an authenticated insider or an attacker reusing stolen/weak credentials rather than an anonymous internet attacker. |
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Alert meAnalysisAIv2 – Oct 18, 2026
A remote authenticated user can crash QNAP Qsync Central 4.x by triggering a NULL pointer dereference, causing a denial of service limited to availability (CVSS 3.1 A:L) with no confidentiality or integrity impact. The vendor fixed the issue in Qsync Central 5.0.0.1 (2025/07/09) and later; no public exploit was identified at time of analysis, and EPSS is 0.15% (35th percentile), consistent with a low-priority issue.
Earlier versions of this analysis (1)
RemediationAI
Vendor-released patch: Qsync Central 5.0.0.1 (2025/07/09) and later, per QNAP advisory QSA-25-34 (https://www.qnap.com/en/security-advisory/qsa-25-34). Because exploitation requires a valid Qsync Central user account, reduce exposure by removing or disabling unused accounts, enforcing least privilege for sync users, and restricting access to Qsync Central to trusted networks or VPN; the trade-off is reduced convenience for remote synchronization. Monitor for repeated Qsync Central crashes or service restarts as a possible indicator of attempts against unpatched instances.
Affected VersionsENISA
Affects your stack
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Technical ContextAI · show details
Qsync Central is QNAP's file synchronization service, and the flaw is a CWE-476 NULL pointer dereference that can terminate or destabilize the service when a crafted request reaches vulnerable code. The CVSS 4.0 vector shows AV:N/AC:L/AT:N/PR:L/UI:N with VA:L only, and the independent CVSS 3.1 assessment agrees: network-reachable exploitation requires a valid Qsync Central user account, no user interaction, and no special configuration, but the impact ceiling is availability only. CPE data scopes the affected software to cpe:2.3:a:qnap:qsync_central, and EUVD record EUVD-2025-32474 lists Qsync Central 4.x before 5.0.0.1 (2025/07/09) as affected.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Authenticated user account needed so PR:L; network-reachable and no user interaction (AV:N/AC:L/UI:N); NULL deref causes only partial availability loss (A:L), no C/I impact.
Primary rating from Vendor (qnapsecurity).
CVSS VectorVendor: qnapsecurity
Lifecycle Timeline
3DescriptionCVE.org
A NULL pointer dereference vulnerability has been reported to affect Qsync Central. If a remote attacker gains a user account, they can then exploit the vulnerability to launch a denial-of-service (DoS) attack.
We have already fixed the vulnerability in the following version: Qsync Central 5.0.0.1 ( 2025/07/09 ) and later
Executive ViewAI
Organizations using A NULL pointer dereference vulnerability should be aware of notable risk from CVE-2025-44008, a null pointer dereference vulnerability rated CVSS 6.5. Exploitation could compromise the security of affected deployments. Organizations should apply vendor updates when available and monitor for exploitation.
Apply vendor patch. If patching is delayed: enable ASLR/DEP, apply network segmentation.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
A null pointer dereference occurs when a program attempts to access memory through a pointer that has been set to NULL (address 0x0).
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
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EUVD-2025-32474
NVD
CVE.org
EPSS
GitHub PoC
Exploit-DB