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TI-2025-43916 Aliases CVE-2025-29896GHSA-p2j4-rcc2-w382

NULL pointer dereference in QNAP Qsync Central qsyncsrv.cgi

Priority LOW 12CWE-476Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · Low
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-476.

Summary

QNAP Qsync Central versions from 5.0.x before 5.0.0.4 contain a NULL pointer dereference in qsyncsrv.cgi, a flaw where the software uses a pointer without checking that it is valid. A remote attacker who holds a user account can trigger a crash that causes a denial-of-service condition. The vulnerability is tracked as CWE-476.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

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 5.0.0.4 and later

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00275 20th percentileScored 2026-11-07
Fix Fixed Qsync Central (QNAP Systems Inc.): 5.0.0.4

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
QNAPQsync Central5.0.x to before 5.0.0.45.0.0.4Patch availableCNA
  • Qsync Central VendorQNAP Affected 5.0.x to before 5.0.0.4 Fixed in 5.0.0.4 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:qnap:qsync_central:*:*:*:*:*:*:*:*——QNAP
  • cpe:2.3:a:qnap:qsync_central:*:*:*:*:*:*:*:* Versions — — ·QNAP

Remediation

Update Qsync Central to version 5.0.0.4 or later.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA Qsync Central (QNAP Systems Inc.) Fixed in 5.0.0.4

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    QNAP Systems Qsync Central 5.0.0.4

    3 records Highest priority Priority LOW 3 LOW

    Other records, highest priority first

    • TI-2025-43917 Stack-based buffer overflow in QNAP Qsync CentralPriority LOW 12
    • TI-2025-43915 Qsync Central NULL pointer dereference allows denial of servicePriority LOW 12
    Show all 3 records →

Timeline

  1. 2026-10-15 Threatist record created from CVE-2025-29896
  2. 2026-10-16 Alias added: GHSA-p2j4-rcc2-w382
  3. 2026-10-16 CISA SSVC decision points changed

References

Other 1

  • TI-2022-10581 DeadBolt Ransomware KEVCVSS 3.1CRITICAL 10.0
  • TI-2021-09791 Improper Authorization Vulnerability in HBS 3 (Hybrid Backup Sync) KEVCVSS 3.1CRITICAL 10.0
  • TI-2020-02221 Command Injection Vulnerability in QTS and QuTS hero KEVCVSS 3.1CRITICAL 9.8
  • TI-2019-05103 Path traversal in QNAP NAS devices running Photo Station KEVCVSS 3.1CRITICAL 9.8
  • TI-2019-05102 Path traversal in QNAP NAS devices running Photo Station KEVCVSS 3.1CRITICAL 9.8
  • TI-2019-05101 Improper input validation in QNAP NAS devices KEVCVSS 3.1CRITICAL 9.8
See all 681 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences