CVE-2026-81516 is a high-severity (CVSS 7.5) CWE-755 vulnerability. No vendor fix is recorded yet; mitigation options are listed below.
Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. From 4.0.0 until 4.3.0, ConsulDiscoveryClient constructs…
Description
Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. From 4.0.0 until 4.3.0, ConsulDiscoveryClient constructs ConsulServiceInstance objects by parsing each registration's secure metadata with a strict Boolean conversion. A principal that can register a Consul service can supply a secure value other than true or false, causing the exception from one instance to abort construction of the entire instance list and make the targeted service undiscoverable. When GetAllInstancesAsync enumerates all services, one malformed instance can abort enumeration across every service. The outage persists until the offending registration is removed. This issue is fixed in version 4.3.0.
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Remediation status
No patched version of the affected component has shipped for CVE-2026-81516 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-81516 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-81516. 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-2026-81516 in your dependencies?
O3 Security finds CVE-2026-81516 across dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.