Critical

CVE-2026-5526 — Tenda 4G03 Pro httpd access control

A security flaw has been discovered in Tenda 4G03 Pro up to 1.0/1.1/04.03.01.53/192.168.0.1. Affected by this vulnerability is an unknown functionality of the file /bin/httpd. The manipulation results in improper access controls. The attack may be performed from remote. The exploit has been released to the public and may be used for attacks.

Published Apr 4, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: VulDB

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.6% (30-day exploitation probability)+7
Technical severity (critical)+10
Automatable exploitation (SSVC)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.65%

ahead of 50% of scored CVEs · Oct 14, 2026

Affects

Tenda

4G03 Pro and 1 more

CVSS base

9.8

Critical · 3 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation

None

none · proof-of-concept · active

Automatable

Yes

can an attacker script the kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Tenda 4G03 Pro, Tenda 4g03 Pro Firmware).
The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Tenda	4G03 Pro	version 04.03.01.41version 04.03.01.27version 04.03.01.28version 04.03.01.29version 04.03.01.30version 04.03.01.31version 04.03.01.32version 04.03.01.33 and 50 more version 04.03.01.34version 04.03.01.35version 04.03.01.36version 04.03.01.37version 04.03.01.38version 04.03.01.39version 04.03.01.40version 04.03.01.26version 04.03.01.42version 04.03.01.43version 04.03.01.44version 04.03.01.45version 04.03.01.46version 04.03.01.47version 04.03.01.48version 04.03.01.49version 04.03.01.50version 04.03.01.51version 04.03.01.52version 04.03.01.53version 192.168.0.0version 192.168.0.1version 04.03.01.12version 1.0version 1.1version 04.03.01.0version 04.03.01.1version 04.03.01.2version 04.03.01.3version 04.03.01.4version 04.03.01.5version 04.03.01.6version 04.03.01.7version 04.03.01.8version 04.03.01.9version 04.03.01.10version 04.03.01.11version 04.03.01.13version 04.03.01.14version 04.03.01.15version 04.03.01.16version 04.03.01.17version 04.03.01.18version 04.03.01.19version 04.03.01.20version 04.03.01.21version 04.03.01.22version 04.03.01.23version 04.03.01.24version 04.03.01.25	Vulnerable	CVE Program (cve.org) e CISA ADP
Tenda	4g03 Pro Firmware	version 04.03.01.53	Vulnerable	NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Network

Attack complexity

Low

Privileges required

None

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
6.9	CVSS 4.0	Medium	—	—	VulDB via CVE Program (cve.org) e CISA ADP
5.5	CVSS 4.0	Medium	—	—	cna@vuldb.com via NIST National Vulnerability Database
9.8	CVSS 3.1	Critical	3.9	5.9	nvd@nist.gov via NIST National Vulnerability Database
7.3	CVSS 3.1	High	3.9	3.4	cna@vuldb.com via NIST National Vulnerability Database
7.3	CVSS 3.1	High	—	—	VulDB via CVE Program (cve.org) e CISA ADP
7.3	CVSS 3.0	High	—	—	VulDB via CVE Program (cve.org) e CISA ADP
7.5	CVSS 2.0	High	10.0	6.4	cna@vuldb.com via NIST National Vulnerability Database
7.5	CVSS 2.0	High	—	—	VulDB via CVE Program (cve.org) e CISA ADP

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov)

Scoring entities (NIST, CNA, ADP) score independently; each score is shown with its origin. For prioritization we use 9.8 (NVD (NIST)) as a conservative provisional reference — not a definitive official score.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-266

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.65%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).

web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

2026
Affected products added · tenda/4g03 pro
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 13, 2026
CVSS changed · 9.8
Oct 13, 2026 · NIST National Vulnerability Database
Source status changed · → Analyzed
Oct 13, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 13, 2026 · NIST National Vulnerability Database
CVE published
Apr 4, 2026 · VulDB

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

4 on the record

vuldb.com/vuln/355279/cti
Permissions Required, VDB Entry, signature, permissions-required, NIST National Vulnerability Database
vuldb.com/vuln/355279
Third Party Advisory, VDB Entry, vdb-entry, NIST National Vulnerability Database
vuldb.com/submit/782052
Third Party Advisory, VDB Entry, third-party-advisory, NIST National Vulnerability Database
www.tenda.com.cn/
Product, product, NIST National Vulnerability Database

Elsewhere on this site

Tenda
every CVE for this vendor

CWE-266
other pages naming this weakness

Related CVEs (same products)

Medium CVE-2026-5527 Tenda 4G03 Pro ECDSA P-256 Private Key server.key hard-coded key Apr 4, 2026
High CVE-2025-15371 Tenda i24 Shadow File hard-coded credentials Dec 30, 2025

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No fixed version, patch or mitigation documented.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-5526 is "Tenda 4G03 Pro httpd access control", rated Critical. It affects 4G03 Pro (Tenda); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 9.8 describes technical severity. EPSS 0.65% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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