Tenda AC8 IPv6 check_is_ipv6 ip address for authentication

published 2026-03-16 7 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-12470

cvss: 9.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.3%; EPSS 1.3% chance of exploitation in 30 days, percentile 70%
public exploits: 0; none known

A vulnerability was identified in Tenda AC8 16.03.50.11. Affected by this issue is the function check_is_ipv6 of the component IPv6 Handler. The manipulation leads to reliance on ip address for authentication. It is possible to initiate the attack remotely. The exploit is publicly available and might be used.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: yes
Technical impact: total
Assessed: 7 mo ago (2026-03-16)

Exploit prediction

1.31% chance of exploitation in the next 30 days, higher than 70% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/digitalandrew/tenda_ac8_v5/blob/main/poc_ipv6_auth_bypass.py referenced PoC, tagged "exploit" by a source, unverified
vuldb.com https://vuldb.com/?submit.771759 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	9.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P
CNA	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:W/RC:R
CNA	3.0	9.8	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:W/RC:R
CNA	2.0	10.0	AV:N/AC:L/Au:N/C:C/I:C/A:C/E:POC/RL:W/RC:UR
CNA	4.0	8.9	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/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
CNA	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA	2.0	10.0	AV:N/AC:L/Au:N/C:C/I:C/A:C

Affected products

Tenda AC8

Classification

Weakness

CWE-291 Reliance on IP Address for Authentication
CWE-287 Improper Authentication

References

github.com /digitalandrew/tenda_ac8_v5/blob/main/poc_ipv6_auth_bypass.py
exploit
vuldb.com /?submit.771759
third-party-advisory, exploit, vdb-entry
vuldb.com /?id.351210
vdb-entry, technical-description, third-party-advisory
vuldb.com /?ctiid.351210
signature, permissions-required, vdb-entry
tenda.com.cn /
product

Sources

CVE List CVE-2026-4252
NVD CVE-2026-4252

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary