CVE-2024-11667: Zyxel Multiple Firewalls Path Traversal Vulnerability

Is it exploited?

Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 3 Dec 2024, 6 days after the CVE record was published.

How likely is exploitation in the next 30 days?

2.9%

EPSS score, percentile 87 of all scored records

How severe?

7.5 High

CVSS v3.1 base score, given by the CNA

What should I do?

CISA deadline 24 Dec 2024. Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Advisories and patches (1)

Which versions are affected?

Affected

• versions V5.00 through V5.38
• versions V5.00 through V5.38
• versions V5.10 through V5.38
• versions V5.10 through V5.38

Versions by product

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

What to do

CISA due date for this action: 24 December 2024.

Advisories and patches

• zyxel.com (Vendor advisory)

Linked from CISA's catalog entry

• https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-protecting-against-recent-firewall-threats-11-21-2024
• https://nvd.nist.gov/vuln/detail/CVE-2024-11667

Affected products and versions

As listed in the CVE record.

Versions not listed are: unaffected.

Versions not listed are: unaffected.

Versions not listed are: unaffected.

Versions not listed are: unaffected.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

About this vulnerability

Multiple Zyxel firewalls contain a path traversal vulnerability in the web management interface that could allow an attacker to download or upload files via a crafted URL.

Summary: CISA's KEV catalog, as of 28 Oct 2026.

• CISA added CVE-2024-11667 to its Known Exploited Vulnerabilities (KEV) catalog on 3 Dec 2024.
• CISA marks it as known to be used in ransomware campaigns.
• The due date CISA sets for the required action is 24 Dec 2024.
• The CVE record was published on 27 Nov 2024, 6 days before it was added to KEV.
• The CVE record carries a CVSS v3.1 base score of 7.5 (High), given by its CNA.
• FIRST's EPSS model puts the probability of exploitation in the next 30 days at 2.9% (percentile 87), as of 28 Oct 2026.
• CISA's SSVC assessment in the CVE record: exploitation active, automatable yes, technical impact partial.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.

Description

A directory traversal vulnerability in the web management interface of Zyxel ATP series firmware versions V5.00 through V5.38, USG FLEX series firmware versions V5.00 through V5.38, USG FLEX 50(W) series firmware versions V5.10 through V5.38, and USG20(W)-VPN series firmware versions V5.10 through V5.38 could allow an attacker to download or upload files via a crafted URL.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

Weakness

• CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.

Timeline

More exploited Zyxel vulnerabilities

• CVE-2026-7273: Zyxel GS1900 Series Switches Stack-Based Buffer Overflow Vulnerability (added 21 Sep 2026)
• CVE-2024-40890: Zyxel DSL CPE OS Command Injection Vulnerability (added 11 Feb 2025)
• CVE-2024-40891: Zyxel DSL CPE OS Command Injection Vulnerability (added 11 Feb 2025)
• CVE-2017-6884: Zyxel EMG2926 Routers Command Injection Vulnerability (added 18 Sep 2023)
• CVE-2017-18368: Zyxel P660HN-T1A Routers Command Injection Vulnerability (added 7 Aug 2023)
• CVE-2023-27992: Zyxel Multiple NAS Devices Command Injection Vulnerability (added 23 Jun 2023)