CVE-2026-81516Network attack vector

Service-discovery outage via strict metadata parsing

Published Sep 17, 2026 · Updated Sep 17, 2026

Denial of service in Steeltoe.Discovery.Consul 4.0.0 through 4.2.0 allows attackers to interrupt service discovery via Consul metadata. ConsulDiscoveryClient passes each registration's secure metadata to bool.Parse, so a non-Boolean value throws and aborts construction of the entire instance list. The attacker must be able to register a Consul service; one malformed instance can hide every instance of a targeted service, or halt all-service enumeration, until that registration is removed.

CVSS severity7.5
High
EPSS probability0.61%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Steeltoe.Discovery.Consul 4.0.0 through 4.2.0 allows attackers to interrupt service discovery via Consul metadata. ConsulDiscoveryClient passes each registration's secure metadata to bool.Parse, so a non-Boolean value throws and aborts construction of the entire instance list. The attacker must be able to register a Consul service; one malformed instance can hide every instance of a targeted service, or halt all-service enumeration, until that registration is removed.

The record

CVE
CVE-2026-81516
Published
Sep 17, 2026
Updated
Sep 17, 2026
Vendor
Steeltoe
Product
Security Advisories
Classifications
CWE-755, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 17, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 4.0.0, < 4.3.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Steeltoe · Security Advisoriesversion=>= 4.0.0, < 4.3.0

Published CVSS scores

7.5GitHubCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-755Improper Handling of Exceptional Conditions
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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