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Threats / QNAP / CVE-2020-2509
CVE-2020-2509 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

QNAP Network-Attached Storage (NAS) vulnerability

QNAP NAS devices are vulnerable to command injection attacks that enable remote code execution. The vulnerability has been actively exploited in the wild.

Verdict

Today item — known-exploited.

Unauthenticated or low-privileged attackers can inject arbitrary commands through QNAP NAS interfaces, achieving remote code execution. Active exploitation and high EPSS score indicate immediate risk to exposed devices.

CISA KEV Yes · 2022-04-113EPSS 0.34168 (verify live)4Exploit Weaponized · public PoC5
01

Is it exploitable?

— the evidence, ranked above the score
Exploit available
Fully weaponized — public exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
5 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-04-11).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.34168 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: QNAP, QNAP Network-Attached Storage (NAS). Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-77 Command Injection, CWE-78 OS Command Injection — weakness family: Injection.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.

03

Why it matters

— the attack path, told twice: adversary, then board
1

Front door — unauthenticated access narrative 1

Attacker
I identify a QNAP NAS device exposed on the network or internet.
Business
Inventory and asset visibility gaps leave NAS appliances discoverable by threat actors.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I craft a malicious input containing shell metacharacters to bypass input validation and inject commands.
Business
Insufficient input sanitization in QNAP firmware creates exploitable attack surface.
3

Lateral reach — past segmentation narrative 3

Attacker
I execute arbitrary commands with the privileges of the NAS application process.
Business
Compromised NAS becomes a pivot point for lateral movement and data exfiltration within trusted infrastructure.
4

Data at risk — exfiltration narrative 4

Attacker
I establish persistence and maintain access to stored data and connected systems.
Business
Loss of confidentiality, integrity, and availability of business-critical files and backups.
04

What to do

— defensible action
  • Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05

Coverage & confidence

— what we know, and what we don’t

Established (cited)

  • KEV listing (CISA)
  • EPSS probability (FIRST)
  • Weaponized exploit available (VulnCheck)
  • 5 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Public exploit availability
  • Catalogued by qnap (CNA)
  • Named finder/reporter credit (CVE.org)
  • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
  • Disclosure & credit2
    Catalogued by qnapCNA