CVSS 4.0
7.7 highCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NCVE-2026-115539 Confused Deputy
High (7.7). EPSS 0.2% estimated probability of exploitation activity in the next 30 days.
On this page
SwarmKit's Cluster-API proxy can overwrite a forwarded client's TLS identity with an intermediary manager's identity. WithMetadataForwardTLSInfo replaces outgoing metadata with a copy of the incoming metadata, discarding the redirect guard's changes when built with grpc-go 1.39 or later. During a short window after a leader change, two proxy hops through managers with inconsistent views of the leader can allow an attacker possessing a valid worker node TLS certificate and private key to obtain a manager node certificate for the attacker's own key, escalating privileges from worker to manager. Applications built with an affected SwarmKit version and grpc-go 1.39 or later are impacted.
Severity
- EPSS
- 0.2% estimated probability of exploitation activity in the next 30 days; 12th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CWE
- CWE-441 Unintended Proxy or Intermediary (Confused Deputy)
- OWASP Top 10
- A01:2025 Broken Access Control
- Published
- Modified
- Assigned by
- Docker (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
- docker:docker engine
- moby:moby
- moby:swarmkit
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| moby SwarmKit | before 2.1.3 |
| Docker Engine | 23.0.0 and later |
| Moby | through 2.0.0-beta.28 |
| moby SwarmKit | 1.12.1-0.20220307221335-616e8db4c3b0 and later |
Fix and patched versions
- Alpine, Alpaquita: fixed package versions per release
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Ubuntu | 26.04:LTS, 26.10, Pro:20.04:LTS and 2 more | docker.io, docker.io-app | no fix listed | UBUNTU-CVE-2026-115539 |
| Ubuntu | Pro:16.04:LTS, Pro:18.04:LTS | docker.io | no fix listed | UBUNTU-CVE-2026-115539 |
| Alpine | v3.24 | docker | 29.9.3-r0 | ALPINE-CVE-2026-115539 |
| Azure Linux | 3 | moby-engine | no fix listed | AZL-113567 |
| Alpaquita | stream | docker | 29.9.3-r0 | BELL-CVE-2026-115539 |
From the distributions' data via OSV.dev: Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0; the Alpine secdb, CC BY-SA 4.0; Microsoft's Azure Linux vulnerability data, MIT; BellSoft's OSV database, MIT. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Ubuntu · Alpine · Alpaquita.
Attack patterns (CAPEC)
- CAPEC-219 XML Routing Detour Attacks Likelihood: High · Severity: Medium
- CAPEC-465 Transparent Proxy Abuse Severity: Medium
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.