CVE-2026-81516 json
Steeltoe.Discovery.Consul: malformed 'secure' metadata aborts service instance lookup (DoS)
published last mo. modified last mo. also GHSA-67c9-f6v2-qv86 , EUVD-2026-81900
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 49%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- nuget Steeltoe.Discovery.Consul 4.3.0
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- last mo.
Exploit prediction
0.61% chance of exploitation in the next 30 days, higher than 49% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| GitHub | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| nuget | Steeltoe.Discovery.Consul | >=4.0.0, <4.3.0 |
4.3.0 |
Affected products
- SteeltoeOSS security-advisories
Classification
- Weakness
-
- CWE-755 Improper Handling of Exceptional Conditions
References
-
github.com
/SteeltoeOSS/Steeltoe/commit/028569c4f4f0e9e393e3c22a4fa5d07987dd8673
web
-
github.com
/SteeltoeOSS/security-advisories/security/advisories/GHSA-67c9-f6v2-qv86
web
-
github.com
/SteeltoeOSS/Steeltoe/releases/tag/4.3.0
web
-
nvd.nist.gov
/vuln/detail/CVE-2026-81516
advisory
-
github.com
/SteeltoeOSS/security-advisories
package
Sources
- CVE List CVE-2026-81516
- GitHub Advisory GHSA-67c9-f6v2-qv86
- NVD CVE-2026-81516
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