CVE-2026-20321 is a vulnerability in Cisco Application Policy Infrastructure Controller
Published on October 7, 2026
Cisco Application Policy Infrastructure Controller API Command Injection Vulnerability
A vulnerability in the web-based management API for Cisco Application Policy Infrastructure Controller (APIC) could allow an authenticated, remote attacker to execute arbitrary commands as the root user. To exploit this vulnerability, the attacker must have valid administrative credentials.
This vulnerability is due to insufficient input validation of user-controlled command arguments. An attacker could exploit this vulnerability by authenticating using the API and sending crafted input. A successful exploit could allow the attacker to execute arbitrary commands on the underlying operating system of an affected device with root-level privileges.
Vulnerability Analysis
CVE-2026-20321 can be exploited with network access, and requires user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a high impact on confidentiality and integrity, and no impact on availability.
Weakness Type
Missing Standardized Error Handling Mechanism
The software does not use a standardized method for handling errors throughout the code, which might introduce inconsistent error handling and resultant weaknesses. If the application handles error messages individually, on a one-by-one basis, this is likely to result in inconsistent error handling. The causes of errors may be lost. Also, detailed information about the causes of an error may be unintentionally returned to the user.
Products Associated with CVE-2026-20321
Want to know whenever a new CVE is published for Cisco Application Policy Infrastructure Controller? stack.watch will email you.
Affected Versions
Cisco Application Policy Infrastructure Controller (APIC):- Version 5.3(1d) is affected.
- Version 5.3(2a) is affected.
- Version 5.3(2b) is affected.
- Version 5.3(2c) is affected.
- Version 5.3(2d) is affected.
- Version 5.3(2e) is affected.
- Version 5.3(2f) is affected.
- Version 6.1(5e) is affected.
- Version 6.2(1f) is affected.
- Version 6.2(1g) is affected.
- Version 6.2(2e) is affected.