What changed in Consul from 1 to 2

2.0.3 (August 7, 2026)

SECURITY:

• Update brace-expansion to address GHSA-rgw5-rvv9-x895 (DoS via unbounded intermediate arrays). [GH-23786]
• Update fast-uri to address GHSA-7p8r-x3mc-p8w7 (Host Confusion via backslash authority introducer). [GH-23786]
• Update golang.org/x/text to v0.39.0 to address GO-2026-5970. [GH-23761]
• Update google.golang.org/grpc to v1.82.1 to address GHSA-hrxh-6v49-42gf. [GH-23761]
• Update socket.io-parser to address CVE-2026-69185 (Zero-attachment Memory Exhaustion). [GH-23786]
• Upgrade to use Go 1.26.5. This resolves vulnerabilities GO-2026-4970 (os). GO-2026-5856 (crypto/tls). [GH-23761]
• agent: Fixed a denial-of-service vulnerability where GET /v1/agent/connect/ca/roots and POST /v1/agent/connect/authorize used the agent-side cache unconditionally, even when http_config { use_cache = false } was configured by the operator. A remote caller could bypass this setting and grow the agent cache without bound by varying the request ACL token. Both endpoints now skip the cache and issue a direct RPC when use_cache is disabled. (SECVULN-50292, SECVULN-50293) [GH-23797]
• agent: Fixed a nil-pointer dereference panic in ShadowServiceRouterConfigEntry.CheckEnt when a service-router config entry contained a route with a nil Destination. A crafted snapshot restore or replication message containing such an entry could crash the FSM decode path. The nil guard now treats a missing destination as non-enterprise data and continues decoding safely. (SECVULN-50291) [GH-23797]
• agent: Fixed a security bypass where a user-supplied public listener (envoy_public_listener_json) with an HTTP Connection Manager filter would skip Consul's inbound request-normalization defaults. An attacker could exploit the un-normalized path to bypass L7 intention deny rules using percent-encoded path equivalents. Consul now injects path normalization (enabled by default, unless the mesh config option InsecureDisablePathNormalization is set) on every HCM filter chain in user-provided public listeners before L7 intention enforcement is applied. (SECVULN-50295) [GH-23797]
• agent: Fixed an unauthenticated denial-of-service vulnerability where PUT /v1/agent/check/update/:id, PUT /v1/agent/check/register, PUT /v1/agent/service/register, and POST /v1/agent/connect/authorize decoded unbounded JSON request bodies before resolving the caller's ACL token. An unauthenticated caller could retain multiple large JSON decoder buffers concurrently inside the Consul process before each request was rejected with HTTP 403, causing attacker-controlled heap growth. All four endpoints now cap the request body at 512 KiB before any decoding occurs, returning HTTP 413 for oversized bodies. This limit applies to chunked transfer encoding as well as declared Content-Length. (SECVULN-50418) [GH-23796]
• agent: Fixed an unauthenticated denial-of-service vulnerability where the external gRPC and gRPC-TLS listeners accepted an unlimited number of TCP connections per source IP before any request processing, ACL check, or rate limiting could occur. A remote attacker could exhaust agent file descriptors, goroutines, and memory by opening many connections and withholding the gRPC or TLS handshake. A new per-client-IP connection limiter is now applied before the gRPC server observes the connection, controlled by the new limits.grpc_max_conns_per_client configuration option (default 100). The gRPC handshake timeout has also been reduced from the library default of 120 seconds to 20 seconds. (SECVULN-50294) [GH-23797]

IMPROVEMENTS:

• ui: migrate yadda/Gherkin acceptance tests to native QUnit (harness, intentions/create, components, settings) [GH-23741]
• xds: Add two new opt-in ProxyDefaults.spec.config keys for controlling the server response header on API Gateway HTTP listeners: envoy_suppress_envoy_headers (removes the header entirely) and envoy_server_header_name (renames it to a custom value). If both are set, suppress takes precedence. [GH-13027]

BUG FIXES:

• agent: Stop logging the raw ACL token in debug-level content-type logs. [GH-23731]
• api-gateway: Fixed a regression that caused an HTTP API gateway to reject its configuration with an "inconsistent protocols" error (resulting in intermittent 503s) when a backend service's service-router composed a route to a destination in a different service, namespace, or partition during discovery-chain synthesis. [GH-23793]
• serf: Fix WAN flood-join to ignore non-alive destination members (leaving/left/failed), allowing rejoined servers to heal back to alive in WAN membership. [GH-23709]
• xds: Addition of XFCC headers to GPRC request similar to HTTP request for connect-proxy inbound listener [GH-23744]

2.0.2 (July 8, 2026)

SECURITY:

• Upgrade alpine base image version to 3.24 to address [CVE-2026-41989], [ALPINE-CVE-2026-2100]. [GH-23711]
• dependency: Upgrade Serf and Memberlist to use the latest versions. [GH-23704]
• xds: Return errors when injecting the L4 intention (RBAC) filter or the mTLS transport socket onto an inbound public listener, so the listener is not served without intention enforcement or mTLS. [GH-23686]

FEATURES:

• config-entry(api-gateway): (Enterprise only) Add ExtAuthzFilter to HTTPRoute Filters and gateway-wide ExtAuthz toggle to the api-gateway config entry [GH-23703]
• config-entry: (Enterprise only) Addition of External Processor (ext_proc) Envoy Extension support to api-gateway and connect-proxy [GH-23705]

IMPROVEMENTS:

• ci: upgrade GitHub Actions that used the deprecated Node 20 runtime to Node 24, and restore GOTOOLCHAIN=auto after setup-go so backward-compatibility and integration test lanes resolve the correct Go toolchain. [GH-23687]
• connect: update support for nomad and vault version to v2.0.3 [GH-23624]
• deps: Migrate armon/go-metrics to hashicorp/go-metrics and update Go dependencies across all modules [GH-23635]

BUG FIXES:

• xds: only emit the client cert SDS block when both CertFile and KeyFile are set. [GH-23679]

KNOWN ISSUES:

• consul-k8s: In setups using consul OSS version, consul-k8s-connect-injector fails to come up because of a missing CRD RouteExtProc. A new version(2.0.2-oss) of consul helm chart is released to resolve this issue. Use the Chart version '2.0.2-oss' for OSS distribution of consul of this release v2.0.2.
• consul (enterprise only): Since (2.0.0) API-GW understands traffic routing via discovery chain configs(resolvers, routers, splitters) attached to services in its route-match destinations. API gateways understands listeners on a hostname basis and compiles overall traffic routing rules for services pointed in the routes for those listeners. A bug surfaced when the destination service has defined failovers/redirects/subsets with targets in different namespace/partition in its resolvers config. The reconciliation of overall discovery chain for all routable targets of api gateway post this feature encounters issues due to missing synthetic defaults for protocols in the said use case and causes xds rendering issues.

2.0.1 (June 18, 2026)

SECURITY:

• Upgrade go version to 1.26.4 to address GO-2026-5039, GO-2026-5038,GO-2026-5037 [GH-23637]
• connect: Upgrade envoy version to 1.37.4, 1.36.8, 1.35.12; Add new version of Envoy 1.38.2 and remove 1.34.14 [GH-23664]

IMPROVEMENTS:

• dockerfile: layer reduction by merging RUN commands and minor changes following best practices. [GH-23650]
• product-telemetry: product usage reporting now preserves export cadence across restarts and leader re-elections by resuming from the last successful export time, preventing delays
• server: Auth method TokenNameFormat field accepts OIDC and JWT claim mapping values [GH-23616]
• ui: Removed block-slot addon dependency [GH-23481]

BUG FIXES:

• connect: Strip the x-forwarded-client-cert header from inbound HTTP requests before forwarding them to local service instances. [GH-23544]
• server: Fixed a bug where renaming a server (or wiping and rejoining it with the same IP and Raft node ID) could cause an out-of-order serf event to evict the live leader from the internal server lookup, resulting in Raft leader not found in server lookup mapping (HTTP 500) errors on follower RPCs until the next member event resynced the mapping. [GH-23533]

2.0.0 (May 22, 2026)

SECURITY:

• connect: Upgrade envoy version to 1.37.2 and newer versions [GH-23469]
• go: Upgrade go version to 1.26 [GH-23493]
• agent: Increased default HTTP server timeouts to prevent breaking long-polling blocking queries. read_timeout and write_timeout are now set to 15 minutes (up from 30 seconds), while read_header_timeout (10s) and idle_timeout (120s) still provide protection against Slowloris attacks. All timeouts remain configurable via the http_config block. [GH-23267]
• api-gateway, terminating-gateway: Apply HTTP request path normalization on api-gateway and terminating-gateway HTTP listeners to prevent L7 intention RBAC bypass via non-normalized paths (CVE-2024-10005). [GH-23534]
• docker: update ubi base image to ubi9-minimal:9.7. [GH-23553]
• docker: Upgrade curl to >= 8.20.0 from Alpine edge in the container image to address CVE-2026-6429, CVE-2026-4873, CVE-2026-5773, CVE-2026-6253, CVE-2026-6276, CVE-2026-7168, CVE-2026-5545. Alpine 3.23 stable does not yet carry the patched version. [GH-23750]
• docker: Update to UBI base image to 9.8 for fixing [CVE_2026-2100] [GH-23588]

FEATURES:

• (Enterprise Only) update to go-licensing/v4 and go-census/v3 inorder to adapt to new licenses of PAO.
• Global Rate Limiter: (Enterprise Only) a new "rate-limit" config entry kind that enables dynamic, cluster-wide RPC rate limiting stored in Raft and automatically replicated to all servers. This allows operators to apply or adjust global rate limits at runtime without restarting Consul servers — a critical capability for emergency scenarios where the cluster is under excessive load.
• api-gateway: Added SDS certificate support for API Gateway listeners, including listener-level default TLS certificates and HTTP/TCP route service TLS SDS overrides. Service overrides inherit the listener SDS cluster when omitted, and gateway validation/xDS generation now rejects conflicting override mappings to keep certificate selection deterministic. [GH-23354]
• api-gateway: add support for gateway-level default upstream limits and route service-level limit overrides for MaxConnections, MaxPendingRequests, and MaxConcurrentRequests. [GH-23396]
• api: Added new API "/v1/internal/rpc/methods" that lists all RPC method names. Requires an operator:read ACL token. This is useful when users want to configure rate limits that exclude specific RPC endpoints. [GH-23329]
• ca: (Enterprise Only) Added new Connect CA provider for Cyberark WIM (connect.ca_provider = "pan-distributed-issuer"), enabling Consul to issue certificates through Cyberark WIM.
• server: (Enterprise Only) add stable cluster identity and leader-gated global registry sync for service summary publishing.
• telemetry: (Enterprise Only) Product telemetry for self-managed Consul with anonymous, opt-in usage reporting.
• mesh: (Enterprise Only) Introduce support for multi-port (named port) services in Consul, including the ability to specify and route traffic using port names, as well as to retrieve virtual IPs for specific service ports. It also enforces that certain advanced multi-port features are only available in Consul Enterprise, and includes new utility functions for cluster naming and ALPN protocol generation.

IMPROVEMENTS:

• agent: (Enterprise Only) Add eventually-consistent background cache for Enterprise usage metrics, reducing GET /v1/operator/usage latency from O(PNK) to O(1) and lowering CPU/memory pressure during high-frequency scraping via a watch-driven maintainer goroutine.
• mesh: (Enterprise Only) Introduce support for multi-port (named port) services in Consul, including the ability to specify and route traffic using port names, as well as to retrieve virtual IPs for specific service ports. It also enforces that certain advanced multi-port features are only available in Consul Enterprise, and includes new utility functions for cluster naming and ALPN protocol generation.
• terminating-gateway: Updated the cluster upstream tls to use sds instead of static certs, allowing for dynamic certificate updates without needing to restart the terminating gateway. [GH-23288]
• telemetry: Add certificate expiry monitoring with Prometheus metrics (labeled with datacenter/partition/namespace), structured logging with configurable severity thresholds, and enhanced Connect CA API to include NotAfter field for root and intermediate certificates. [GH-23147]
• deps: Upgrade github.com/hashicorp/vault/sdk from v0.7.0 to v0.25.1 and github.com/hashicorp/vault/api from v1.12.2 to v1.16.0. [GH-23574]
• test-integ: upgrade testcontainers-go (v0.22.0->v0.40.0) and docker/docker (v24.0.5->v28.5.1) in the integration test module. This removes opencontainers/runc as a Go dependency of the test framework. These are test infrastructure dependencies only and have no impact on the consul binary or any consul deployment. [GH-23573]
• xds: add Consecutive5xx, ConsecutiveGatewayFailure, and EnforcingConsecutiveGatewayFailure fields to PassiveHealthCheck, allowing operators to configure Envoy outlier detection thresholds for 5xx responses and gateway failures (502/503/504) on upstreams defaults.

BUG FIXES:

• audit-logging: (Enterprise Only) Fixed JSON unmarshall error when array of obj is passed for auditReq body.
• cli: Enhanced error messages in consul config write command to provide actionable guidance when config entries cannot be modified due to references by gateways or routers. [GH-22921]
• xds: Fixed XDS package to generate correct endpoints and cluster configurations for API Gateways when peered, and updated the API Gateway update handler to propogate mesh gateway config to its upstreams. [GH-23454]
• XDS: Fixes issue with mesh-gateway in remote mode on AWS EKS, as DNS hostnames are assigned to AWS NLBs instead of IPs and envoy's EDS endpoint validation expects address to be an IP. Now EDS load assignment is skipped for non-peer remote mesh gateway targets with hostname based gateways keeping CDS/EDS in sync. [GH-23543]
• api-gateway: resolve service subsets for routes during API gateway discovery chain synthesis. [GH-23294]
• ui: Fix broken documentation links [GH-23578]