CVE-2026-39993

Path Traversal to Root RCE in QNAP Download Station via Addon/Search addon Parameter

CVSS score

8.7

EPSS probability

—

Risk score

0.9

Published

2 h ago

Overview Public Exploits (0)Newsroom Vulnerability Timeline

Patch status has not yet been verified

Resmî kaynaklarda yeterli kanıt bulunamadı. Bu sonuç “yama yok” anlamına gelmez.

Impact on My Inventory

Only the personal products you have added to your account are assessed; an organisation's inventory does not appear here.

Checking session…

Vulnerability description

CVE AI research

The stored explanation is shown at once; refreshing evaluates the sources again.

DayBreach AI Explanation

Verified against sources

CVE-2026-39993 Relative Path Traversal Vulnerability in Download Station

Sources read

Source agreement

Tam uyum

Evidence confidence

%55

Short explanation

CVE-2026-39993 is a relative path traversal vulnerability affecting Download Station [S0]. It allows remote attackers to read the contents of unexpected files or system data [S0].

Why does it matter?

It enables an authenticated attacker to read sensitive system data, leading to potential confidentiality breaches [S0].

What should be done?

Update to Download Station 5.10.2.313 or later [S0]
Update to Download Station 5.11.3.322 or later [S0]
Follow vendor advisories [S0]

Chain of evidence and sources2 verified claims

Download Station, göreceli yol gezinmesi açığı barındırmaktadır [S0].

S0 · daybreach-canonical S1 · nvd

Saldırganın kullanıcı hesabı edinmesi durumunda açık istismar edilebilir [S0].

S0 · daybreach-canonical S1 · nvd

Show the technical text from the sources

A relative path traversal vulnerability has been reported to affect Download Station. If a remote attacker gains a user account, they can then exploit the vulnerability to read the contents of unexpected files or system data. We have already fixed the vulnerability in the following version: Download Station 5.10.2.313 and later Download Station 5.11.3.322 and later

CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

CWE: CWE-23

Explanation produced with the local gemini-flash-lite-latest model. Numerical metrics and the KEV, patch and exploit statuses are not determined by AI.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-39993 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

ID	VENDOR	PRODUCT	ACTION
1	QNAP Systems Inc.	Download Station	View

Total affected vendors: 1|Products: 1

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCORE	VERSION	SEVERITY	VECTOR	SOURCE
8.7	CVSS V40	HIGH	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X	NVD
8.7	CVSS V4_0	HIGH	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N	CVE CNA

Patch and Remediation Guide

Solution & Remediation Advisory

Patch status unknown

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Confirm the affected product and version against the source evidence above.

Restrict access to internet-facing services and apply network segmentation.

Until a patch is confirmed, follow the vendor advisory; do not read an unknown status as “no patch”.

Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-39993 is associated with the following CWEs:

CWE-23: Common Weakness Enumeration Entry CWE-23

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-39993 weaknesses.

CAPEC-66: SQL Injection CAPEC-126: Path Traversal CAPEC-28: OS Command Injection

Attack Vector and Accessibility

ExposureAğ üzerinden

PermissionsLow

UserGerekmiyor

Official Sources and Advisories

https://www.qnap.com/en/app_releasenotes/list.php?app_choose=DownloadStationvendor-advisory

CVSS Vector Radar Chart

8.7 / 10

Vulnerability Scoring Details

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredLow privileges

User InteractionNone required

Confidentiality (Gizlilik)Low

Integrity (Bütünlük)None

Availability (Erişilebilirlik)High

Yama durumu bilinmiyor

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Follow the vendor

QNAP Systems Inc.

Weakness Type (CWE & CAPEC)

CWE-23

Similar Vulnerabilities

9.8

CVE-2018-19949 Actively exploited

Path Traversal leading to Arbitrary File Move, Docker Escape, and Host RCE in /calapi/renameUpload endpoint

VendorQNAP Systems Inc.ProductQcalAgent

Patch status unknown2 h ago

7.7

CVE-2025-66275

Remote code execution via command injection

VendorQNAP Systems Inc.ProductVideo Station

Patch status unknown3 h ago

7.7

CVE-2025-66272

Arbitrary file deletion and remote code execution