CVE-2026-71920CWE-476

CVE-2026-71920

Medium · published August 24, 2026

CVSS v3.1
4.9
EPSS
1%
Percentile
45.6
In the wild
Unconfirmed
What it is

Multiple DrayTek VigorSwitch models contain a null pointer dereference vulnerability in the formlogout function. The vulnerability is caused by missing checks for an empty or absent Cookie header before string handling. A remote attacker can trigger this vulnerability via a crafted request to crash the service and cause a denial of service. Exploitation requires valid administrative credentials for the device's web management interface.

The record
Technical detail
CVSS v3.1
4.9 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
6.9 · CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
EPSS
0.00556 · 45.6th percentile
Weakness
CWE-476 · NULL Pointer Dereference
Published
2026-08-24T22:17Z
References (2)
https://www.draytek.com/about/security-advisory/multiple-vulnerabilities-in-vigorswitch-series-august-2026/ · [email protected]https://www.vulncheck.com/advisories/draytek-vigorswitch-multiple-models-null-pointer-dereference-via-formlogout · [email protected]
EPSS history
Timeline
  • 26 AUG 08:24Z
    EPSS moved — → 0%
    epss
  • 24 AUG 17:07Z
    DrayTek VigorSwitch Multiple Models NULL Pointer Dereference via formlogout
    cvelistv5