CVE-2026-84479

Published Sep 1, 2026

Last updated a month ago

CVSS critical 9.3
XSS

Overview

Description
WWBN AVideo (current e01e41ecc and earlier) makes three login-time security controls depend solely on the client-supplied User-Agent header. The isAVideoEncoder()/isAVideoMobileApp() checks match HTTP_USER_AGENT against a hardcoded literal ("AVideoEncoder"/"AVideoMobileApp") with no IP check or shared secret. An attacker who submits valid credentials and sets User-Agent: AVideoEncoder bypasses two-factor authentication, skips brute-force captcha escalation, and avoids being recorded in the login/device audit history. No patch is available at the time of publication.
Source
disclosure@vulncheck.com
NVD status
Deferred

Risk scores

CVSS 4.0

Type
Secondary
Base score
9.3
Impact score
-
Exploitability score
-
Vector string
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Severity
CRITICAL

CVSS 3.1

Type
Secondary
Base score
9.1
Impact score
5.2
Exploitability score
3.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Severity
CRITICAL

Weaknesses

disclosure@vulncheck.com
CWE-290

Social media

Hype score
Not currently trending

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References

Sources include official advisories and independent security research.