SB2023091421 - Time-of-check Time-of-use (TOCTOU) Race Condition in Cisco IOS XR Software



SB2023091421 - Time-of-check Time-of-use (TOCTOU) Race Condition in Cisco IOS XR Software

Published: September 14, 2023

Security Bulletin ID SB2023091421
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Code execution

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Time-of-check Time-of-use (TOCTOU) Race Condition (CVE-ID: CVE-2023-20135)

CWE-ID: CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local user to execute arbitrary code on the system.

The vulnerability exists due to a time-of-check, time-of-use (TOCTOU) race condition when an install query regarding an ISO image is performed during an install operation that uses an ISO image. A local administrator can execute arbitrary code on target system.


Remediation

Install update from vendor's website.