CVE-2018-25318
Auth Bypass in Tenda Fh303 Firmware 5.07.68_en
Raw vector
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: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:XCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2018-25318 is a critical-severity Authentication Bypass by Spoofing (CWE-290) vulnerability in Tenda Fh303 Firmware. Its CVSS base score is 9.3 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Adversary-in-the-Middle (T1557); ranked at the 50th 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-2 (Identification and Authentication (Organizational Users)) and IA-3 (Device Identification and Authentication) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2018-25318 is a session weakness vulnerability in Tenda FH303/A300 firmware version V5.07.68_EN, arising from insufficient cookie validation. This flaw allows unauthenticated attackers to modify DNS settings on affected devices.
Remote attackers with network access can exploit the vulnerability by sending crafted GET requests to the /goform/AdvSetDns endpoint, using a spoofed admin cookie. Successful exploitation enables attackers to alter DNS servers, redirecting user traffic to malicious sites and potentially enabling further attacks like phishing or malware distribution. The issue carries a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), reflecting critical severity across confidentiality, integrity, and availability impacts, and is associated with CWE-290.
Relevant advisories and resources include an exploit entry on Exploit-DB at https://www.exploit-db.com/exploits/44381 and a Vulncheck advisory at https://www.vulncheck.com/advisories/tenda-fh303-a300-68-en-cookie-session-weakness-dns-change.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2018-21839
Vulnerability Data
Tenda FH303/A300 firmware V5.07.68_EN contains a session weakness vulnerability that allows unauthenticated attackers to modify DNS settings by exploiting insufficient cookie validation. Attackers can send GET requests to the /goform/AdvSetDns endpoint with a crafted admin cookie to change DNS servers…
more
and redirect user traffic to malicious sites.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 3 hardening rules · 3 OS baselines
V6.4.3V10.4.16V10.5.1V11.4.3
Mitigating Controls (NIST 800-53 r5) AI
Proper unique identification and authentication of users directly stops spoofing-based bypass of authentication.
Device identification and authentication before connection prevents spoofing of devices to bypass auth.
Authentication of non-organizational users blocks external spoofing attempts against the scheme.
Authenticator management ensures credentials cannot be easily spoofed or reused to bypass authentication.
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.
Proofing and binding identities reduces spoofing opportunities during enrollment but does not address runtime authentication implementation flaws.
Requiring authentication of users/services/hardware directly counters spoofing-based bypass when strong methods are used.
Protecting, conveying, and verifying identity assertions specifically prevents the spoofing that enables authentication bypass.
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.
Access control policy reduces spoofing opportunities but does not prescribe authentication mechanisms.
Identity management supports unique identities but does not guarantee resistance to spoofing.
Authentication information management directly addresses credential handling that prevents spoofing.
Access rights assignment limits exposure but does not enforce authentication strength.
Privileged access rights reduce attack surface but do not prevent spoofing of authentication.
Network security can limit spoofing vectors but does not address application-level authentication.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (higher-evidence rows only; rows rated `none` are excluded).
Oracle Linux 8 (1 rule)
- V-248827 OL 8 must not have the rsh-server package installed. prevents CWE-290
RHEL 7 (1 rule)
- V-204442 The Red Hat Enterprise Linux operating system must not have the rsh-server package installed. prevents CWE-290
RHEL 8 (1 rule)
- V-230492 RHEL 8 must not have the rsh-server package installed. prevents CWE-290