High · CVSS 7.0CVE-2026-115538

Docker Engine overlay-network encryption rules are not restored after a firewalld reloadCVE-2026-115538

Answer in brief

CVE-2026-115538 records a High severity (CVSS 7.0) vulnerability in Docker Engine overlay-network encryption rules are not restored after a firewalld reload. The current sources do not mark it as known exploited. The current feed maps Docker/Docker Engine (generic), Moby/Moby (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Nov 10, 2026Updated Nov 10, 2026Source checked Nov 10, 2026First seen by HOL Nov 10, 2026Material review Nov 10, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 7.0
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 7.0. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Docker/Docker Engine (generic), Moby/Moby (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Docker/Docker Enginegeneric	>=0 <29.9.3	29.9.3
Moby/Mobygeneric	>=0 <v2.0.0-beta.29	v2.0.0-beta.29

Recommended response

Check inventory. Check lockfiles and deployed manifests for Docker/Docker Engine, Moby/Moby.
Review the reported fix. Source-reported workaround: Configure firewalld to preserve other applications' iptables rules: use FirewallBackend=nftables with a build that includes commit b7faa74db15e2d1ebd9fdfcdc7579874d3a2fa87 (firewalld 2.0.0 or later, or the RHEL backports listed in configurations), and remove all firewalld direct configuration. Alternatively, restart dockerd after every firewalld reload, stop, or start to restore the encryption rules; this also restarts the node's Swarm tasks. As defense in depth, block incoming traffic to the VXLAN port (by default, UDP port 4789) at the Internet boundary. This prevents injection from outside the boundary but does not protect the confidentiality of traffic between nodes.

Evidence timeline and material changes

Published upstream
Nov 10, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Nov 10, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Nov 10, 2026

Sources and claim methodology

GitHub security advisorygithub.com

Upstream source description

Moby's overlay network driver does not restore the iptables rules for encrypted overlay networks after firewalld deletes them. Unlike other Docker Engine networking components, the overlay driver does not handle firewalld reload or start signals over D-Bus. The missing rules cause outgoing VXLAN datagrams to bypass IPsec encryption and remove the protection against incoming cleartext VXLAN traffic. The condition is not logged by dockerd and persists until the encrypted network's last local endpoint is removed and another is added, or dockerd is restarted. Each further firewalld event repeats the condition.

Quoted source text, attributed separately from HOL analysis.

Affected scope and exposure questions

The current feed maps Docker/Docker Engine (generic), Moby/Moby (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Docker/Docker Enginegeneric	>=0 <29.9.3	29.9.3
Moby/Mobygeneric	>=0 <v2.0.0-beta.29	v2.0.0-beta.29

Recommended response

Check inventory. Check lockfiles and deployed manifests for Docker/Docker Engine, Moby/Moby.

Review the reported fix. Source-reported workaround: Configure firewalld to preserve other applications' iptables rules: use FirewallBackend=nftables with a build that includes commit b7faa74db15e2d1ebd9fdfcdc7579874d3a2fa87 (firewalld 2.0.0 or later, or the RHEL backports listed in configurations), and remove all firewalld direct configuration. Alternatively, restart dockerd after every firewalld reload, stop, or start to restore the encryption rules; this also restarts the node's Swarm tasks. As defense in depth, block incoming traffic to the VXLAN port (by default, UDP port 4789) at the Internet boundary. This prevents injection from outside the boundary but does not protect the confidentiality of traffic between nodes.

Sources and claim methodology

Upstream source description

Quoted source text, attributed separately from HOL analysis.