How severe is CVE-2024-6343?

CVE-2024-6343 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2024-6343 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-6343?

CVE-2024-6343 affects Zyxel Zld. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-6343?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2024-6343 have an EU (EUVD) identifier?

Yes. CVE-2024-6343 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-47456.

When was CVE-2024-6343 published?

CVE-2024-6343 was published on 2024-09-03 and last updated on 2026-06-17.

CVE-2024-6343

CVE-2024-6343 is a medium-severity vulnerability in Zyxel Zld with a CVSS 3.x base score of 4.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-120.

Key facts

Severity: Medium (CVSS 3.x base score 4.9)
EPSS exploit prediction: 1% (45th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-47456
Weakness: CWE-120
Affected product: Zyxel Zld
Published: 2024-09-03
Last modified: 2026-06-17

Description

A buffer overflow vulnerability in the CGI program of Zyxel ATP series firmware versions from V4.32 through V5.38, USG FLEX series firmware versions from V4.50 through V5.38, USG FLEX 50(W) series firmware versions from V4.16 through V5.38, and USG20(W)-VPN series firmware versions from V4.16 through V5.38 could allow an authenticated attacker with administrator privileges to cause denial of service (DoS) conditions by sending a crafted HTTP request to a vulnerable device.

Frequently asked questions

What is CVE-2024-6343?: A buffer overflow vulnerability in the CGI program of Zyxel ATP series firmware versions from V4.32 through V5.38, USG FLEX series firmware versions from V4.50 through V5.38, USG FLEX 50(W) series firmware versions from V4.16 through V5.38, and USG20(W)-VPN series firmware versions from V4.16 through V5.38 could allow an authenticated attacker with administrator privileges to cause denial of service (DoS) conditions by sending a crafted HTTP request to a vulnerable device.
How severe is CVE-2024-6343?: CVE-2024-6343 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2024-6343 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-6343?: CVE-2024-6343 affects Zyxel Zld. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-6343?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-6343 have an EU (EUVD) identifier?: Yes. CVE-2024-6343 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-47456.
When was CVE-2024-6343 published?: CVE-2024-6343 was published on 2024-09-03 and last updated on 2026-06-17.

References

https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-in-firewalls-09-03-2024

Affected products (1)

cpe:2.3:o:zyxel:zld:*:*:*:*:*:*:*:*

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