NVD / CVE Program· CNA Zyxel

CVE-2024-0816: The buffer overflow vulnerability in the DX3300-T1 firmware version V5.50(ABVY.4)C0 could allow an authenticated local attacker to cause den

Noroxi assessment

Priority: Monitor (action score 22/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.14% (FIRST EPSS).
Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
According to the record, no fixed version is available yet.
Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Update when a fix is released; follow the vendor's advisory.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

The buffer overflow vulnerability in the DX3300-T1 firmware version V5.50(ABVY.4)C0 could allow an authenticated local attacker to cause denial of service (DoS) conditions by executing the CLI command with crafted strings on an affected device.

MediumCVSS 5.5 · v3.1—No exploit No fix recorded

Published: May 20, 2024
Updated: Jun 17, 2026
EPSS: 0.1% · 3th percentile
CWE: CWE-120

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 22 / 40 · 5.5 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.1%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · Zyxel: 5.5; NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
No fixed version yet

If any of these changes, we'll tell you in the daily email digest.

Running WordPress? Scan your site free with WP Lens

Is your version affected? Check it

Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

We use this product, ask for help

Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
zyxel	lte3202-m437 firmware	cpe:2.3:o:zyxel:lte3202-m437_firmware
zyxel	lte3202-m437	cpe:2.3:h:zyxel:lte3202-m437
zyxel	lte3301-plus firmware	cpe:2.3:o:zyxel:lte3301-plus_firmware
zyxel	lte3301-plus	cpe:2.3:h:zyxel:lte3301-plus
zyxel	lte5388-m804 firmware	cpe:2.3:o:zyxel:lte5388-m804_firmware
zyxel	lte5388-m804	cpe:2.3:h:zyxel:lte5388-m804
zyxel	lte5398-m904 firmware	cpe:2.3:o:zyxel:lte5398-m904_firmware
zyxel	lte5398-m904	cpe:2.3:h:zyxel:lte5398-m904
zyxel	lte7240-m403 firmware	cpe:2.3:o:zyxel:lte7240-m403_firmware
zyxel	lte7240-m403	cpe:2.3:h:zyxel:lte7240-m403
zyxel	lte7480-m804 firmware	cpe:2.3:o:zyxel:lte7480-m804_firmware
zyxel	lte7480-m804	cpe:2.3:h:zyxel:lte7480-m804

and 118 more

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

zyxel ax7501-b0 firmware5.17(abpc.4)c0
zyxel ax7501-b1 firmware5.17(abpc.4)c0
zyxel dx3300-t1 firmware5.50(aby.4)c0
zyxel dx3301-t0 firmware5.50(aby.4)c0
zyxel dx4510 firmware5.17(abyl.6)c0
zyxel dx5401-b0 firmware5.17(abyo.5)c0
zyxel dx5401-b1 firmware5.17(abyo.5)c0
zyxel emg3525-t50b firmware5.50(abpm.8)c0
zyxel emg5523-t50b firmware5.50(abpm.8)c0
zyxel emg5723-t50k firmware5.50(abom.8.2)c0
zyxel ex3300-t1 firmware5.50(aby.4)c0
zyxel ex3301-t0 firmware5.50(aby.4)c0
zyxel ex3320-t0 firmware5.71(yak.2)d0
zyxel ex3320-t1 firmware5.71(yap.0)c0
zyxel ex3500-t0 firmware5.44(achr.0)c0
zyxel ex3501-t0 firmware5.44(achr.0)c0
zyxel ex3510 firmware5.17(abup.11)c0
zyxel ex5401-b0 firmware5.17(abyo.5)c0
zyxel ex5401-b1 firmware5.17(abyo.5)c0
zyxel ex5501-b0 firmware5.17(abry.4)c0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Zyxel). Independent of NVD's CPE analysis and usually ahead of it.

Zyxel DX3300-T1 firmware
- V5.50(ABVY.4)C0affected

Same product

zyxel: all records

Other highest-scoring records for the same primary product.

CVE-2023-22920A security misconfiguration vulnerability exists in the Zyxel LTE3316-M604 firmware version V2.00(ABMP.6)C0 due to a factory default misconf
39Monitor
CVE-2022-43389A buffer overflow vulnerability in the library of the web server in Zyxel NR7101 firmware prior to V1.15(ACCC.3)C0, which could allow an una
39Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

CVE-2022-43389496 days apartA buffer overflow vulnerability in the library of the web server in Zyxel NR7101 firmware prior to V1.15(ACCC.3)C0, which could allow an una
39Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

TR-24-0515 · May 21, 2024(Zyxel Güvenlik Bildirimi )

All national notices →

Technical details

Attack conditions

Someone with local access to the system can trigger it.
A low-privileged account is enough.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: none
Integrity: none
Availability: high · the service can be disrupted

Attack vector: Local
Attack complexity: Low
Privileges required: Low
User interaction: None
Scope: Unchanged
Confidentiality impact: None
Integrity impact: None
Availability impact: High

Weakness class (CWE)

CWE-120 · Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

nvd-secondary

Root cause

When data is copied, the source length is not compared with the size of the destination buffer. Excess data overwrites adjacent memory.

The bug in code

The whole CWE-120 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1char buf[256];
2memcpy(buf, pkt->data, pkt->len);

Fixed

1char buf[256];
2if (pkt->len > sizeof(buf)) {
3  return -EINVAL;
4}
5memcpy(buf, pkt->data, pkt->len);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

—

Change log

No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

References

www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-buffer-overflow-vulnerabilities-in-some-5g-nr-4g-lte-cpe-dsl-ethernet-cpe-fiber-ont-wifi-extender-and-home-router-devices-05-21-2024

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records