CVE-2026-35406 is a medium-severity (CVSS 6.2) Uncontrolled Resource Consumption vulnerability in netavark. A fix is available for netavark — see the affected versions and patch details below.
Aardvark-dns has incorrect error handling for malformed tcp packets
Exploitation Status
No confirmed exploitation observed yet
- 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-2026-35406.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-35406 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 376,715 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
netavarkReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
Aardvark-dns is an authoritative dns server for A/AAAA container records. From 1.16.0 to 1.17.0, a truncated TCP DNS query followed by a connection reset causes aardvark-dns to enter an unrecoverable infinite error loop at 100% CPU. This vulnerability is fixed in 1.17.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | netavark | ≥ 1.16.0&&< 1.17.1 | 1.17.1cargo update -p netavark --precise 1.17.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for netavark, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update netavark to 1.17.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-35406 is resolved across your whole dependency graph.
Workarounds
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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-35406 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-35406. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Enterprise Linux 10 | aardvark-dns-2:1.17.1-1.el10_2 | RHSA-2026:36782 |
| Red Hat Enterprise Linux 9 | aardvark-dns-2:1.17.1-1.el9_8 | RHSA-2026:36318 |
Frequently Asked Questions
Is CVE-2026-35406 in your dependencies?
O3 Security finds CVE-2026-35406 across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.