Cyber Resilience

CVE-2025-9091

Exposed Creds in Tenda Ac20 Firmware 16.03.08.12

Public PoCExposed Creds
Published
17 August 2025
Modified
17 June 2026
Patch / advisory
CVSS Score v4 1.1
Click a component to see what it means
Raw vectorCVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/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
EPSS Score 0.0022 13th percentile
Risk Priority 14 floored blend · peak EPSS

Summary

CVE-2025-9091 is a low-severity Use of Hard-coded Password (CWE-259) vulnerability in Tenda Ac20 Firmware. Its CVSS base score is 1.1 (Low).

Operationally, exploitation aligns with the MITRE ATT&CK technique Unsecured Credentials (T1552); ranked at the 13th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to IA-5 (Authenticator Management) and SC-12 (Cryptographic Key Establishment and Management) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A security flaw has been discovered in Tenda AC20 16.03.08.12. Affected by this vulnerability is an unknown functionality of the file /etc_ro/shadow. The manipulation leads to hard-coded credentials. It is possible to launch the attack on the local host. The…

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complexity of an attack is rather high. The exploitation appears to be difficult. The exploit has been disclosed to the public and may be used.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1552 Unsecured Credentials Credential Access
Adversaries may search compromised systems to find and obtain insecurely stored credentials.
T1552.001 Credentials In Files Credential Access
Adversaries may search local file systems and remote file shares for files containing insecurely stored credentials.
T1078 Valid Accounts Stealth
Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
T1078.001 Default Accounts Stealth
Adversaries may obtain and abuse credentials of a default account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
T1552.004 Private Keys Credential Access
Adversaries may search for private key certificate files on compromised systems for insecurely stored credentials.
T1133 External Remote Services Persistence
Adversaries may leverage external-facing remote services to initially access and/or persist within a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-9731Same vendor: Tenda
CVE-2025-9791Same product: Tenda Ac20
CVE-2025-11385Same product: Tenda Ac20
CVE-2025-9090Same product: Tenda Ac20
CVE-2025-9089Same product: Tenda Ac20
CVE-2025-14654Same product: Tenda Ac20
CVE-2025-14655Same product: Tenda Ac20
CVE-2026-1610Same vendor: Tenda
CVE-2025-15356Same product: Tenda Ac20
CVE-2025-9088Same product: Tenda Ac20

Affected Assets

tenda
ac20 firmware
16.03.08.12

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

Authenticator management requires secure distribution and handling of credentials, structurally discouraging hard-coded values.

Cryptographic key management mandates proper establishment and handling instead of embedding keys in code.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly prohibit embedding credentials in source code or binaries.

PR.AA-01 partial match
prevents

PR.AA-01's credential/key-management processes can reduce the incentive to embed secrets but do not address or detect hard-coded values in source code, so the weakness remains fully possible.

PR.AA-02 none match
prevents

PR.AA-02 addresses human identity proofing and per-person credential issuance at enrollment; it has no bearing on whether developers embed static credentials in software.

PR.DS-01 none match
prevents

PR.DS-01 addresses encryption and integrity of stored data but never touches credential or key management practices, so it neither prevents hard-coded credentials nor removes any of their risk.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Education on secure configuration practices discourages technical staff from embedding or relying on hard-coded credentials in systems and applications.

mitigates

Secure key-generation, distribution and storage procedures reduce the likelihood that hard-coded or default cryptographic keys will be introduced or left unprotected.

prevents

Explicit prohibition of hard-coded passwords and unauthenticated external services stops credentials from being embedded directly in source code.

prevents

Contractual requirements for secure coding practices and evidence of testing make it less likely that hard-coded credentials will be introduced or remain undetected in delivered code.

none

Requiring independent oversight and timely disabling of non-human identities makes it harder for hard-coded or long-lived credentials to remain exploitable.

prevents

Requiring users to change temporary or default passwords at first use stops the continued existence of hard-coded or guessable passwords that are shipped with the product.

References