Security Resilience

CVE-2023-35086

Asus Rt-Ac86U Firmware 3.0.0.4_386_51529

Published
21 July 2023
Modified
21 November 2024
CVSS Score v3.1 7.2
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.39 99th percentile
Risk Priority 78 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-2023-35086 is a high-severity Use of Externally-Controlled Format String (CWE-134) vulnerability in Asus Rt-Ac86U Firmware. Its CVSS base score is 7.2 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique LSASS Memory (T1003.001); ranked in the top 1% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

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 format string vulnerability exists in the do_detwan_cgi module of httpd on ASUS RT-AX56U V2 and RT-AC86U routers. The flaw is caused by the logmessage_normal function directly passing untrusted input as a format string to syslog and affects firmware versions 3.0.0.4.386_50460 on the RT-AX56U V2 and 3.0.0.4_386_51529 on the RT-AC86U.

A remote attacker who already possesses administrator credentials can exploit the weakness over the network to achieve arbitrary code execution, arbitrary system operations, or denial of service.

Public advisories published by TWCERT at the referenced URLs describe the issue and affected firmware but do not provide additional mitigation details beyond the CVE record. The associated EPSS score has remained at its peak value of 0.7589 since disclosure.

EU & UK References

Vulnerability Data

It is identified a format string vulnerability in ASUS RT-AX56U V2 & RT-AC86U. This vulnerability is caused by directly using input as a format string when calling syslog in logmessage_normal function, in the do_detwan_cgi module of httpd. A remote attacker…

more

with administrator privilege can exploit this vulnerability to perform remote arbitrary code execution, arbitrary system operation or disrupt service. This issue affects RT-AX56U V2: 3.0.0.4.386_50460; RT-AC86U: 3.0.0.4_386_51529.

CWE(s)
CWE-134

Related Threats

MITRE ATT&CK Enterprise Techniques

T1003.001 LSASS Memory Credential Access
Adversaries may attempt to access credential material stored in the process memory of the Local Security Authority Subsystem Service (LSASS).
attack.mitre.org →
T1003.002 Security Account Manager Credential Access
Adversaries may attempt to extract credential material from the Security Account Manager (SAM) database either through in-memory techniques or through the Windows Registry where the SAM database is stored.
attack.mitre.org →
T1003.004 LSA Secrets Credential Access
Adversaries with SYSTEM access to a host may attempt to access Local Security Authority (LSA) secrets, which can contain a variety of different credential materials, such as credentials for service accounts.
attack.mitre.org →
T1003.007 Proc Filesystem Credential Access
Adversaries may gather credentials from the proc filesystem or `/proc`.
attack.mitre.org →
T1005 Data from Local System Collection
Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.
attack.mitre.org →
T1016 System Network Configuration Discovery Discovery
Adversaries may look for details about the network configuration and settings, such as IP and/or MAC addresses, of systems they access or through information discovery of remote systems.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-35087Same product: Asus Rt-Ac86U
CVE-2023-39239Same product: Asus Rt-Ac86U
CVE-2023-39238Same product: Asus Rt-Ac86U
CVE-2023-39240Same product: Asus Rt-Ac86U
CVE-2023-41349Same vendor: Asus
CVE-2023-28703Same product: Asus Rt-Ac86U
CVE-2023-39236Same product: Asus Rt-Ac86U
CVE-2023-38031Same product: Asus Rt-Ac86U
CVE-2023-38032Same product: Asus Rt-Ac86U
CVE-2023-39237Same product: Asus Rt-Ac86U

Affected Assets

asus
rt-ac86u firmware
3.0.0.4_386_51529
asus
rt-ax56u v2 firmware
3.0.0.4.386_50460

Mitigating Controls

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.

ID.RA-01 partial match
blocks

Vulnerability identification can discover existing format-string flaws but does not prevent their introduction.

PR.PS-06 partial match
blocks

Secure SDLC practices directly prevent external format strings via code review, static analysis, and safe APIs.

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.5.14 Information transfer partial match
removes
A.5.15 Access control partial match
removes
A.5.16 Identity management partial match
removes
A.5.17 Authentication information partial match
removes
A.5.18 Access rights partial match
removes
A.8.10 Information deletion partial match
removes

References