Skip to content

CVE-20XX-?

CVE-2026-3871

6.5 MEDIUM 0.2% exploit odds No fix listed Memory safety Device

What it is

A buffer overflow vulnerability in the UPnP DeletePortMapping() command in Zyxel VMG4005-B50B firmware versions through 5.13(ABRL.5.4)C0 could allow an adjacent attacker to trigger a temporary denial-of-service (DoS) condition affecting the UPnP function of the affected device.

At a glance

Exploitability: Can be exploited from the same network segment without logging in. High risk of service disruption.
Exploit odds: 0.2% chance of exploitation in the next 30 days (EPSS).
Fix: No patch or advisory is linked yet. Look at mitigations or restrict exposure.

Timeline

2026-06-02 03:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2026-07-22 19:10 UTC Last updatedMost recent change to the record

Details

Published: 2026-06-02 03:16 UTC
Last modified: 2026-07-22 19:10 UTC
Exploit probability: 0.2% · EPSS, next 30 days
Weakness: CWE-120 · Classic buffer overflow
Record status: Deferred

Attack profile CVSS 3.1 · 6.5

Attack vector: Adjacent network
Complexity: Low
Privileges needed: None
User interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

Raw vector

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

Meme: I wake up, CVE-2026-3871

Download Square Reddit

References

https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-buffer-overflow-vulnerabilities-in-the-upnp-function-of-certain-4g-lte-5g-nr-cpe-and-dsl-ethernet-cpe-06-02-2026

NVD record · CVE.org record