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Threats / Zyxel / CVE-2024-11667
CVE-2024-11667 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Zyxel Multiple Firewalls vulnerability

Multiple Zyxel firewalls contain a path traversal vulnerability in the web management interface allowing attackers to download or upload files via crafted URLs.

Verdict

Today item, not a backlog item.

Path traversal in Zyxel firewall web interfaces enables unauthorized file access and modification. Active exploitation and ransomware deployment observed. Immediate patching required for affected firewall models.

CISA KEV Yes · 2024-12-033Ransomware use Flagged3EPSS 0.03017 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
2 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 2024-12-03), flagged for known ransomware use.
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.03017 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Zyxel, Multiple Firewalls. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-22 Path Traversal — weakness family: Path traversal / file.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-22 · Path TraversalPath traversal / file
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 craft a malicious URL with path traversal sequences to bypass directory restrictions on the Zyxel firewall web interface.
Business
Attackers gain unauthorized access to sensitive firewall configuration files and system data.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I upload malicious files to arbitrary locations on the firewall system by exploiting the path traversal flaw.
Business
Compromised firewall becomes a pivot point for lateral movement into the protected network infrastructure.
3

Lateral reach — past segmentation narrative 3

Attacker
I download critical firewall configurations and credentials stored on the device.
Business
Extracted credentials and network topology enable broader organizational compromise.
4

Data at risk — exfiltration narrative 4

Attacker
I deploy ransomware payloads through the compromised firewall to encrypt systems across the network.
Business
Organization faces operational shutdown, data loss, and extortion demands from ransomware operators.
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)
  • Ransomware-use flag (CISA)
  • EPSS probability (FIRST)
  • 2 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Catalogued by Zyxel (CNA)
  • 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.
  • No finder/reporter credit recorded in the public CVE entry — the work behind this find is unattributed.
  • Disclosure & credit2
    Catalogued by ZyxelCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.