What is the CVSS score of CVE-2026-3091?

CVE-2026-3091 has a CVSS 3.1 base score of 6.7 (Medium). CVSS vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.0%.

How to fix or mitigate CVE-2026-3091?

Within 30 days: Identify affected systems running Synology Presto Client and apply vendor patches as part of regular patch cycle. Monitor vendor channels for patch availability.

Synology CVE-2026-3091

MEDIUM

Uncontrolled Search Path Element (CWE-427)

2026-02-24 security@synology.com

Information Disclosure Synology

6.7

CVSS 3.1 · NVD

View

Vulnerability Assessment

Weakness	CWE CWE-427 OWASP Top 10:2025 A08:2025 - Software or Data Integrity Failures ASVS 5.0 V13 - Configuration Search path element control
Impact	CVSS 6.7 (MEDIUM). Attack vector: Local. Complexity: High. Privileges required: Low. User interaction: Required. Exploitable via local access.
Exploit ScenarioDerived	An attacker could exploit this vulnerability to read or write arbitrary files during installation by placing a malicious DLL in.

This Month Plan within 30 days. Why: MEDIUM severity (CVSS 4.0-6.9).

No patch listed yet 0.0% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAIv1 – Mar 12, 2026

Synology Presto Client versions prior to 2.1.3-0672 are vulnerable to DLL hijacking during installation, enabling local attackers with user privileges to read or write arbitrary files by placing malicious libraries in the installer directory. The vulnerability requires user interaction and local access but grants high-impact capabilities including confidentiality and integrity violations. No patch is currently available.

Earlier versions of this analysis (1)

v1 Mar 12, 2026 - 21:55 CVSS 6.7

An uncontrolled search path element vulnerability in Synology Presto Client before 2.1.3-0672 allows local users to read or write arbitrary files during installation by placing a malicious DLL in advance in the same directory as the installer. [CVSS 6.7 MEDIUM]

RemediationAI

Monitor vendor advisories for a patch.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

Classified as CWE-427 (Uncontrolled Search Path Element). Affects Presto Client. An uncontrolled search path element vulnerability in Synology Presto Client before 2.1.3-0672 allows local users to read or write arbitrary files during installation by placing a malicious DLL in advance in the same directory as the installer.

Know when Synology gets its next vulnerability

Watch products and get an email when something new is published
Check this CVE against your own stack and servers
Exploit and PoC references, threat intelligence from 22 sources

Continue with Google Continue with GitHub

No credit card · 7-day full trial

Severity by source

NVD PRIMARY 6.7 MEDIUM

AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector

Local

Attack Complexity

High

Privileges Required

Low

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

DescriptionCVE.org

Executive ViewAI

Why It Matters

Organizations using Synology Presto Client should be aware of notable risk from CVE-2026-3091, a DLL hijacking vulnerability rated CVSS 6.7. Exploitation could compromise the security of affected deployments. Organizations should apply vendor updates when available and monitor for exploitation.

Business Impact: Moderate

Compensating Controls

Apply vendor patch. If patching is delayed: restrict network access and enable monitoring.

Threat Intelligence Overview

EPSS Score

0.0%

Top 98% exploitable

Data Quality

4 sources

Confidence: Medium

NVD

CVE.org

EPSS

VulDB

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.

SignalValue

Severity MEDIUM

CISA KEV No

Public POC No

EPSS 0.0%

Patch available No

Active threat No

Deciding rule

MEDIUM severity (CVSS 4.0-6.9)

What every action level means

Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.

Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.

This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.

This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.

Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

Exploitation· derived

None

System Exposure· derived

Small

Automatable· derived

Priority Score

Low Medium High Critical

KEV: 0

EPSS: 0

CVSS: +34

PoC: 0

Weaponized: 0

Threat intel: 0

Gov advisory: 0

Attack Technique

Information Disclosure MEDIUM

Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.