Arista VeloCloud Orchestrator Improper Input Validation
CVE-2026-93952 is a critical-severity improper input validation vulnerability in VeloCloud Orchestrator (VCO) On-Prem from Arista Networks, with a CVSS 3.1 base score of 10.0 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected VeloCloud Orchestrator (VCO) On-Prem versions: 5.2.0 through 5.2.3.15; 6.1.0 through 6.1.3.7; 6.4.0 through 6.4.2.7, and others listed below. The record does not name a fixed version, so check the vendor advisory. CISA added it to the Known Exploited Vulnerabilities catalogue on September 22, 2026, which means attacks have been observed in the wild.
Attackers are already exploiting this vulnerability, according to CISA.
What to do
- Update Velocloud Orchestrator to 5.2.3.16 or 6.4.2.8, whichever matches your release line, or a later version.
- CISA's required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
- Read the advisory on arista.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Arista Networks | VeloCloud Orchestrator (VCO) On-Prem | 5.2.0 through 5.2.3.15; 6.1.0 through 6.1.3.7; 6.4.0 through 6.4.2.7; 7.0.0 through 7.0.0.2 | Not stated |
| Arista | Velocloud Orchestrator | 5.2.0 up to, but not including, 5.2.3.16; 6.1.0 through 6.1.3.7; 6.4.0 up to, but not including, 6.4.2.8; 7.0.0 through 7.0.0.2 | 5.2.3.16, 6.4.2.8 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H. Scored by CNA (arista.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 9.5 | Critical | CNA (arista.com) |
| CVSS 3.1 | 10.0 | Critical | CNA (arista.com) |
Official description
VeloCloud Orchestrator (VCO) on-prem has a security issue where this issue may allow a remote attacker to access privileged internal functionality and impact the VCO host. Successful exploitation may compromise the confidentiality, integrity, and availability of the orchestrator and data managed by the orchestrator. Hosted, including Dedicated, versions of VCO were impacted and have already been patched.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Input Validation
The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.
How developers prevent this class of flaw
- Consider using language-theoretic security (LangSec) techniques that characterize inputs using a formal language and build recognizers for that language. This effectively requires parsing to be a distinct layer that effectively enforces a boundary between raw input and internal data representations, instead of allowing parser code to be scattered throughout the program, where it could be subject to errors or inconsistencies that create weaknesses.
- Use an input validation framework such as Struts or the OWASP ESAPI Validation API. Note that using a framework does not automatically address all input validation problems; be mindful of weaknesses that could arise from misusing the framework itself (CWE-1173).
- Understand all the potential areas where untrusted inputs can enter the product, including but not limited to: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide data to the application. Remember that such inputs may be obtained indirectly through API calls.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: active, automatable: yes, technical impact: total).
- Added to CISA's Known Exploited Vulnerabilities catalogue.
- Record last changed materially (score, affected products, status or references).
- Deadline for US federal agencies to remediate, set by CISA.
References
Advisories
Third-party and government advisories
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-93952US Government Resource
Our coverage
Recent Improper Input Validation vulnerabilities
- 7.5 High severity
- 9.1 Critical severity
- 9.3 Critical severity
- 7.5 High severity
- 9.9 Critical severity
- 8.5 High severity
Spotted an error? Tell us.