EOS: Improper Neutralization of Special Elements used in an OS Command
CVE-2026-73447 is a critical-severity improper neutralization of special elements used in an OS command vulnerability in EOS from Arista Networks, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. The record lists versions 4.31.0F, 4.32.0F, 4.33.0F as the first without the flaw, so updating EOS to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.7% chance of exploitation within 30 days, higher than 54% of scored CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update EOS to 4.31.0F or 4.32.0F or 4.33.0F, whichever matches your release line, or a later version.
- Read the advisory on arista.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Arista Networks | EOS | 4.30.2F up to, but not including, 4.31.0F; 4.31.0F up to, but not including, 4.32.0F; 4.32.0F up to, but not including, 4.33.0F; 4.33.0F through 4.33.8M; 4.34.0F through 4.34.7M; 4.35.0F through 4.35.5M; 4.36.0F through 4.36.0.1F | 4.31.0F, 4.32.0F, 4.33.0F |
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
- HighAdministrator-level access is required first.
- 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:H/UI:N/S:C/C:H/I:H/A:H. Scored by CNA (arista.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 9.4 | Critical | CNA (arista.com) |
| CVSS 3.1 | 9.1 | Critical | CNA (arista.com) |
Official description
A privileged attacker can exploit certain operation to execute arbitrary commands with root privileges, leading to full device compromise. An authenticated user can exploit gRPC Network Security Interface (gNSI) Certz service on Arista EOS-based products to escalate privileges and execute arbitrary OS commands via a crafted Certz Rotate request. The Bootz service is also affected.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Neutralization of Special Elements used in an OS Command
The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command before it is sent to a downstream component.
How developers prevent this class of flaw
- If at all possible, use library calls rather than external processes to recreate the desired functionality.
- For any data that will be used to generate a command to be executed, keep as much of that data out of external control as possible. For example, in web applications, this may require storing the data locally in the session's state instead of sending it out to the client in a hidden form field.
- For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
More Improper Neutralization of Special Elements used in an OS Command vulnerabilities (CWE-78)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other vulnerabilities in EOS
- 7.5 High severity
- 8.6 High severity
- 8.6 High severity
- 9.6 Critical severity
- 8.6 High severity
- 8.2 High severity
Recent Improper Neutralization of Special Elements used in an OS Command vulnerabilities
- 8.8 High severity
- 9.8 Critical severity
- 9.8 Critical severity
- 7.5 High severity
- 7.8 High severity
- 9.1 Critical severity
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