CVE-2023-39240: Detailed Vulnerability Analysis and Overview

CVE-2023-39240 Vulnerability Summary

It is identified a format string vulnerability in ASUS RT-AX56U V2’s iperf client function API. This vulnerability is caused by lacking validation for a specific value within its set_iperf3_cli.cgi module. A remote attacker with administrator privilege can exploit this vulnerability to perform remote arbitrary code execution, arbitrary system operation or disrupt service.

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CVE-2023-39240: Detailed Information and External References

EPSS

0.00064

EPSS %

0.29917

References

0.00064

• https://www.twcert.org.tw/tw/cp-132-7356-021bf-1.html
• https://www.twcert.org.tw/tw/cp-132-7356-021bf-1.html

CWE

CWE-134

CAPEC

0.00064

• Format String Injection: An adversary includes formatting characters in a string input field on the target application. Most applications assume that users will provide static text and may respond unpredictably to the presence of formatting character. For example, in certain functions of the C programming languages such as printf, the formatting character %s will print the contents of a memory location expecting this location to identify a string and the formatting character %n prints the number of DWORD written in the memory. An adversary can use this to read or write to memory locations or files, or simply to manipulate the value of the resulting text in unexpected ways. Reading or writing memory may result in program crashes and writing memory could result in the execution of arbitrary code if the adversary can write to the program stack.
• String Format Overflow in syslog(): This attack targets applications and software that uses the syslog() function insecurely. If an application does not explicitely use a format string parameter in a call to syslog(), user input can be placed in the format string parameter leading to a format string injection attack. Adversaries can then inject malicious format string commands into the function call leading to a buffer overflow. There are many reported software vulnerabilities with the root cause being a misuse of the syslog() function.

Vulnerable Configurations

• cpe:2.3:o:asus:rt-ax55_firmware:3.0.0.4.386_50460:*:*:*:*:*:*:*
  cpe:2.3:o:asus:rt-ax55_firmware:3.0.0.4.386_50460:*:*:*:*:*:*:*
• cpe:2.3:h:asus:rt-ax55:-:*:*:*:*:*:*:*
  cpe:2.3:h:asus:rt-ax55:-:*:*:*:*:*:*:*
• cpe:2.3:o:asus:rt-ax56u_v2_firmware:3.0.0.4.386_50460:*:*:*:*:*:*:*
  cpe:2.3:o:asus:rt-ax56u_v2_firmware:3.0.0.4.386_50460:*:*:*:*:*:*:*
• cpe:2.3:h:asus:rt-ax56u_v2:-:*:*:*:*:*:*:*
  cpe:2.3:h:asus:rt-ax56u_v2:-:*:*:*:*:*:*:*
• cpe:2.3:o:asus:rt-ac86u_firmware:3.0.0.4_386_51529:*:*:*:*:*:*:*
  cpe:2.3:o:asus:rt-ac86u_firmware:3.0.0.4_386_51529:*:*:*:*:*:*:*
• cpe:2.3:h:asus:rt-ac86u:-:*:*:*:*:*:*:*
  cpe:2.3:h:asus:rt-ac86u:-:*:*:*:*:*:*:*

CVSS3 Source

twcert@cert.org.tw

CVSS3 Type

Secondary

CVSS3 Vector

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H