CVE intelligence and bounded remediation
CVE-2026-20199 — Cisco Thousandeyes Virtual Appliance security vulnerability
A vulnerability in the SSL certificate handling of Cisco ThousandEyes Virtual Appliance could allow an authenticated, remote attacker to execute commands on the underlying operating system as the root user. This vulnerability is due to insufficient validation of user-supplied input. An authenticated attacker could exploit this vulnerability by uploading a crafted certificate to an affected device. A successful exploit could allow the attacker to execute arbitrary code as the root user on the underlying operating system. To exploit this vulnerability, the attacker must have valid administrative credentials.
- Severity
- High
- CVSS
- 7.2 (3.1)
- Published
- 2026-05-20
- CISA KEV
- Not currently listed
- Ecosystem
- software/application
- Weaknesses
- CWE-74
Affected products
- cisco / thousandeyes_virtual_appliance
Matched remediation archetype
Command, code, expression, and template injection
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Trace untrusted values to process execution, interpreters, evaluators, template engines, dynamic imports, and administrative scripting features.
- Determine whether the affected path is reachable across each trust boundary and which service account or host privilege it inherits.
- Review configuration for optional execution features, unsafe compatibility modes, and shell invocation.
Remediate safely
- Replace string-built commands or evaluated code with fixed operations and structured argument APIs that do not invoke a shell.
- Use strict allowlists for operation identifiers and reject unexpected input before it reaches any interpreter.
- Update the affected component and add inert regression tests covering metacharacters, encoding variants, and alternate request paths.
Authoritative sources
Complete CVE record and remediation plan
The detailed catalog view below loads this exact record, its source evidence, and the full seven-phase agentic change plan.