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
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
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 |
Affected Products
aardvark-dnscontainersDetection & 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
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.
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.
This vulnerability is evaluated as having a Moderate severity because the affected service is only exposed locally within user-defined Podman container networks, preventing untrusted remote network exploitation. An attacker must already control a container running on the internal network to deliver the malformed TCP…
As a mitigation, avoid using aardvark-dns when container name resolution is not required by creating Podman networks with DNS disabled (e.g., podman network create --disable-dns). This prevents the vulnerable component from being used.Source: Red Hat security advisory for CVE-2026-35406 (CC BY 4.0)
| 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 |
| Red Hat Hardened Images | aardvark-dns-main-2.1.0-1.hum1 | RHSA-2026:56999 |
Frequently Asked Questions
Is CVE-2026-35406 in your dependencies?
Find it across crates.io, including transitive dependencies.