CVE-2026-73439
HIGHCVE-2026-73439 is a high-severity (CVSS 7.5) CWE-842 vulnerability. O3 Security confirms whether CVE-2026-73439 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
On affected platforms running Arista EOS, if OpenConfig is configured and running a gNMI server on the system, and if gNSI Pathz is configured and a gNSI Pathz policy is present on…
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-73439.
Description
On affected platforms running Arista EOS, if OpenConfig is configured and running a gNMI server on the system, and if gNSI Pathz is configured and a gNSI Pathz policy is present on the system, then gNMI may fail to correctly enforce the rules in this policy if both a group rule and a user rule for the same path is present in the policy. Under certain conditions, this can lead to an authenticated user gaining unauthorized permission to read or write gNMI paths that the Pathz policy is intended to restrict.
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of the affected component has shipped for CVE-2026-73439 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-73439 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-73439. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-73439 in your dependencies?
O3 detects CVE-2026-73439 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.