Security Resilience

CVE-2025-63835

Memory Safety in Tenda Ac18 Firmware 15.03.05.05

Public PoCMemory Safety
Published
10 November 2025
Modified
18 November 2025
CVSS Score v3.1 8.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0069 52th percentile
Risk Priority 65 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2025-63835 is a high-severity Out-of-bounds Write (CWE-787) vulnerability in Tenda Ac18 Firmware. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation of Remote Services (T1210); ranked in the top 48% of CVEs by exploit likelihood; 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 SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — 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.

A stack-based buffer overflow vulnerability, tracked as CVE-2025-63835, affects Tenda AC18 routers running firmware version v15.03.05.05_multi. The issue resides in the guestSsid parameter handled by the /goform/WifiGuestSet web interface, where insufficient bounds checking allows oversized input to overflow the stack buffer. This flaw is associated with CWE-787 (Out-of-bounds Write) and CWE-121 (Stack-based Buffer Overflow), earning a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).

Remote attackers with low privileges, such as authenticated users, can exploit this vulnerability over the network with low complexity and no user interaction required. By sending specially crafted oversized data to the guestSsid parameter, attackers can trigger a denial of service condition causing the device to crash, or potentially achieve remote code execution if the overflow is controlled precisely.

The primary advisory reference is a GitHub report detailing the vulnerability at https://github.com/babraink/cve_report/blob/main/cve_report/tenda/tendaAC18/2_wifiguest_guestssid_overflow/README.md, which security practitioners should consult for exploit details and any recommended mitigations, as no patch information is specified in available data.

EU & UK References

Vulnerability Data

A stack-based buffer overflow vulnerability was discovered in Tenda AC18 v15.03.05.05_multi. The vulnerability exists in the guestSsid parameter of the /goform/WifiGuestSet interface. Remote attackers can exploit this vulnerability by sending oversized data to the guestSsid parameter, leading to denial of…

more

service (device crash) or potential remote code execution.

CWE(s)
CWE-787CWE-121

Related Threats

MITRE ATT&CK Enterprise Techniques

T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
attack.mitre.org →
T1584 Compromise Infrastructure Resource Development
Adversaries may compromise third-party infrastructure that can be used during targeting.
attack.mitre.org →
T1584.008 Network Devices Resource Development
Adversaries may compromise third-party network devices that can be used during targeting.
attack.mitre.org →
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-2485Same product: Tenda Ac18
CVE-2024-2487Same product: Tenda Ac18
CVE-2024-2486Same product: Tenda Ac18
CVE-2024-2558Same product: Tenda Ac18
CVE-2024-33835Same product: Tenda Ac18
CVE-2024-2546Same product: Tenda Ac18
CVE-2025-60660Same product: Tenda Ac18
CVE-2024-2489Same product: Tenda Ac18
CVE-2024-2488Same product: Tenda Ac18
CVE-2024-2547Same product: Tenda Ac18

Affected Assets

tenda
ac18 firmware
15.03.05.05

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 2 hardening rules · 2 OS baselines
Validate
Prove the fix (OWASP ASVS)

—

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and evaluation (including fuzzing and bounds checks) finds out-of-bounds write flaws before deployment.

SI-10 Information Input Validation good match

Input validation directly stops untrusted data from exceeding stack buffer bounds.

SI-16 Memory Protection good match

Memory-protection mechanisms limit the ability to execute injected code after a stack overflow.

SA-15 Development Process, Standards, and Tools partial match

Requiring documented secure-development standards and tools can mandate bounds-checked coding practices that avoid the weakness.

SA-8 Security and Privacy Engineering Principles partial match

Secure-engineering principles include bounds-checked coding and safe buffer handling that avoid introducing the flaw.

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
blocks

Secure-development practices (static analysis, bounds checking, code review) are the primary means of preventing out-of-bounds writes.

ID.RA-01 partial match
blocks

Vulnerability scanning and recording can discover out-of-bounds write flaws so they can be remediated.

PR.PS-02 partial match
blocks

Patching or replacing vulnerable software directly eliminates known instances of this coding weakness.

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.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development and acceptance can detect and prevent out-of-bounds write defects.

A.8.28 Secure coding partial match
prevents

Secure coding directly addresses out-of-bounds writes through language choice and coding standards.

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-248594 OL 8 must implement address space layout randomization (ASLR) to protect its memory from unauthorized code execution. blocks CWE-121
Oracle Linux 9 (1 rule)
  • V-271452 OL 9 must use a Linux Security Module configured to enforce limits on system services. blocks CWE-121

References