Add HTTP/2 header memory exhaustion security documentation#13381
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This PR contains the following updates: | Package | Update | Change | |---|---|---| | [traefik](https://github.com/containous/traefik) | patch | `v3.7.5` → `v3.7.6` | --- >⚠️ **Warning** > > Some dependencies could not be looked up. Check the [Dependency Dashboard](issues/12) for more information. --- ### Release Notes <details> <summary>containous/traefik (traefik)</summary> ### [`v3.7.6`](https://github.com/containous/traefik/blob/HEAD/CHANGELOG.md#v376-2026-06-30) [Compare Source](traefik/traefik@v3.7.6...v3.7.6) [All Commits](traefik/traefik@v3.7.5...v3.7.6) **Bug fixes:** - **\[acme, logs]** Bump github.com/go-acme/lego/v5 ([#​13154](traefik/traefik#13154) [@​ldez](https://github.com/ldez)) - **\[acme]** Bump github.com/go-acme/lego/v5 ([#​13359](traefik/traefik#13359) [@​juliens](https://github.com/juliens)) - **\[k8s, k8s/ingress-nginx]** Fix ingress-nginx ssl passthrough status updates ([#​13212](traefik/traefik#13212) [@​nickmnt](https://github.com/nickmnt)) - **\[k8s/gatewayapi]** Add missing Gateway API features in conformance tests ([#​13356](traefik/traefik#13356) [@​AnatoleLucet](https://github.com/AnatoleLucet)) - **\[k8s/gatewayapi]** Avoid collisions for Gateway API services names ([#​13367](traefik/traefik#13367) [@​rtribotte](https://github.com/rtribotte)) - **\[k8s/gatewayapi]** Ignore other gateways parentRefs and update route parent statuses only for managed gateways ([#​13397](traefik/traefik#13397) [@​rtribotte](https://github.com/rtribotte)) - **\[k8s/ingress-nginx]** Configure retry according to buffering configuration ([#​13039](traefik/traefik#13039) [@​rtribotte](https://github.com/rtribotte)) - **\[k8s/ingress-nginx]** Fix force-ssl-redirect routing 418 when TLS is terminated upstream ([#​13386](traefik/traefik#13386) [@​carloslima](https://github.com/carloslima)) - **\[k8s]** Detect EndpointSlice condition changes ([#​13405](traefik/traefik#13405) [@​kevinpollet](https://github.com/kevinpollet)) - **\[k8s]** Index Kubernetes EndpointSlice by service name ([#​13395](traefik/traefik#13395) [@​kevinpollet](https://github.com/kevinpollet)) - **\[k8s]** Sort endpointslices to keep backend IPs consistent across rebuilds ([#​13406](traefik/traefik#13406) [@​kevinpollet](https://github.com/kevinpollet)) - **\[kv]** Bump kvtools/redis to v1.2.1 ([#​13403](traefik/traefik#13403) [@​ldez](https://github.com/ldez)) - **\[middleware, authentication]** Fix x-forwarded-port in forward-auth ([#​13344](traefik/traefik#13344) [@​juliens](https://github.com/juliens)) - **\[middleware, k8s/gatewayapi]** Fix Gateway API redirect missing statuses ([#​13360](traefik/traefik#13360) [@​AnatoleLucet](https://github.com/AnatoleLucet)) - **\[middleware, k8s/gatewayapi]** Fix Host header not being modified by RequestHeaderModifier ([#​12805](traefik/traefik#12805) [@​mihuross](https://github.com/mihuross)) - **\[middleware, k8s/gatewayapi]** Fix request scheme derivation when Gateway API RequestRedirect omits scheme ([#​13347](traefik/traefik#13347) [@​gndz07](https://github.com/gndz07)) - **\[middleware]** Fix CORS Max-Age set to 0 by default ([#​13371](traefik/traefik#13371) [@​AnatoleLucet](https://github.com/AnatoleLucet)) - **\[middleware]** Fix CORS wildcard when allow-credentials is true ([#​13368](traefik/traefik#13368) [@​AnatoleLucet](https://github.com/AnatoleLucet)) - **\[server]** Add an option to remove request headers with underscores ([#​13262](traefik/traefik#13262) [@​youkoulayley](https://github.com/youkoulayley)) - **\[server]** Configurable max request header size ([#​13353](traefik/traefik#13353) [@​juliens](https://github.com/juliens)) - **\[tls]** Fix nondeterministic TLS certificate selection on shared SAN ([#​13348](traefik/traefik#13348) [@​rtribotte](https://github.com/rtribotte)) - **\[webui]** Bump axios to v1.18.0 ([#​13380](traefik/traefik#13380) [@​gndz07](https://github.com/gndz07)) - **\[websocket]** Fix connection upgrades when backend server is using h2c scheme ([#​12967](traefik/traefik#12967) [@​stffabi](https://github.com/stffabi)) **Documentation:** - **\[k8s/crd]** Fix broken CRD reference links in IngressRoute page ([#​13375](traefik/traefik#13375) [@​s3onghyun](https://github.com/s3onghyun)) - **\[k8s/gatewayapi]** Remove experimental note for Gateway API/TLSRoute documentation ([#​13392](traefik/traefik#13392) [@​jnoordsij](https://github.com/jnoordsij)) - **\[k8s/ingress-nginx]** Add Kubernetes Ingress NGINX to the providers list ([#​13372](traefik/traefik#13372) [@​nmengin](https://github.com/nmengin)) - **\[k8s]** Align Helm chart documented values with chart v41 ([#​13366](traefik/traefik#13366) [@​mloiseleur](https://github.com/mloiseleur)) - **\[middleware, authentication, k8s/ingress-nginx]** Clarify intentional auth-response-headers gating and absence of stripping incoming X-Forwarded-\* headers ([#​13342](traefik/traefik#13342) [@​rtribotte](https://github.com/rtribotte)) - **\[middleware]** Clarify entryPoint middleware reference format ([#​13364](traefik/traefik#13364) [@​mloiseleur](https://github.com/mloiseleur)) - **\[security]** Add HTTP/2 header memory exhaustion security documentation ([#​13381](traefik/traefik#13381) [@​emilevauge](https://github.com/emilevauge)) - Adds documentations on maxHeaderBytes ([#​13363](traefik/traefik#13363) [@​juliens](https://github.com/juliens)) - Fix inaccuracies in reference documentation ([#​13304](traefik/traefik#13304) [@​sheddy-traefik](https://github.com/sheddy-traefik)) ### [`v3.7.6`](https://github.com/containous/traefik/blob/HEAD/CHANGELOG.md#v376-2026-06-30) [Compare Source](traefik/traefik@v3.7.5...v3.7.6) [All Commits](traefik/traefik@v3.7.5...v3.7.6) **Bug fixes:** - **\[acme, logs]** Bump github.com/go-acme/lego/v5 ([#​13154](traefik/traefik#13154) [@​ldez](https://github.com/ldez)) - **\[acme]** Bump github.com/go-acme/lego/v5 ([#​13359](traefik/traefik#13359) [@​juliens](https://github.com/juliens)) - **\[k8s, k8s/ingress-nginx]** Fix ingress-nginx ssl passthrough status updates ([#​13212](traefik/traefik#13212) [@​nickmnt](https://github.com/nickmnt)) - **\[k8s/gatewayapi]** Add missing Gateway API features in conformance tests ([#​13356](traefik/traefik#13356) [@​AnatoleLucet](https://github.com/AnatoleLucet)) - **\[k8s/gatewayapi]** Avoid collisions for Gateway API services names ([#​13367](traefik/traefik#13367) [@​rtribotte](https://github.com/rtribotte)) - **\[k8s/gatewayapi]** Ignore other gateways parentRefs and update route parent statuses only for managed gateways ([#​13397](traefik/traefik#13397) [@​rtribotte](https://github.com/rtribotte)) - **\[k8s/ingress-nginx]** Configure retry according to buffering configuration ([#​13039](traefik/traefik#13039) [@​rtribotte](https://github.com/rtribotte)) - **\[k8s/ingress-nginx]** Fix force-ssl-redirect routing 418 when TLS is terminated upstream ([#​13386](traefik/traefik#13386) [@​carloslima](https://github.com/carloslima)) - **\[k8s]** Detect EndpointSlice condition changes ([#​13405](traefik/traefik#13405) [@​kevinpollet](https://github.com/kevinpollet)) - **\[k8s]** Index Kubernetes EndpointSlice by service name ([#​13395](traefik/traefik#13395) [@​kevinpollet](https://github.com/kevinpollet)) - **\[k8s]** Sort endpointslices to keep backend IPs consistent across rebuilds ([#​13406](traefik/traefik#13406) [@​kevinpollet](https://github.com/kevinpollet)) - **\[kv]** Bump kvtools/redis to v1.2.1 ([#​13403](traefik/traefik#13403) [@​ldez](https://github.com/ldez)) - **\[middleware, authentication]** Fix x-forwarded-port in forward-auth ([#​13344](traefik/traefik#13344) [@​juliens](https://github.com/juliens)) - **\[middleware, k8s/gatewayapi]** Fix Gateway API redirect missing statuses ([#​13360](traefik/traefik#13360) [@​AnatoleLucet](https://github.com/AnatoleLucet)) - **\[middleware, k8s/gatewayapi]** Fix Host header not being modified by RequestHeaderModifier ([#​12805](traefik/traefik#12805) [@​mihuross](https://github.com/mihuross)) - **\[middleware, k8s/gatewayapi]** Fix request scheme derivation when Gateway API RequestRedirect omits scheme ([#​13347](traefik/traefik#13347) [@​gndz07](https://github.com/gndz07)) - **\[middleware]** Fix CORS Max-Age set to 0 by default ([#​13371](traefik/traefik#13371) [@​AnatoleLucet](https://github.com/AnatoleLucet)) - **\[middleware]** Fix CORS wildcard when allow-credentials is true ([#​13368](traefik/traefik#13368) [@​AnatoleLucet](https://github.com/AnatoleLucet)) - **\[server]** Add an option to remove request headers with underscores ([#​13262](traefik/traefik#13262) [@​youkoulayley](https://github.com/youkoulayley)) - **\[server]** Configurable max request header size ([#​13353](traefik/traefik#13353) [@​juliens](https://github.com/juliens)) - **\[tls]** Fix nondeterministic TLS certificate selection on shared SAN ([#​13348](traefik/traefik#13348) [@​rtribotte](https://github.com/rtribotte)) - **\[webui]** Bump axios to v1.18.0 ([#​13380](traefik/traefik#13380) [@​gndz07](https://github.com/gndz07)) - **\[websocket]** Fix connection upgrades when backend server is using h2c scheme ([#​12967](traefik/traefik#12967) [@​stffabi](https://github.com/stffabi)) **Documentation:** - **\[k8s/crd]** Fix broken CRD reference links in IngressRoute page ([#​13375](traefik/traefik#13375) [@​s3onghyun](https://github.com/s3onghyun)) - **\[k8s/gatewayapi]** Remove experimental note for Gateway API/TLSRoute documentation ([#​13392](traefik/traefik#13392) [@​jnoordsij](https://github.com/jnoordsij)) - **\[k8s/ingress-nginx]** Add Kubernetes Ingress NGINX to the providers list ([#​13372](traefik/traefik#13372) [@​nmengin](https://github.com/nmengin)) - **\[k8s]** Align Helm chart documented values with chart v41 ([#​13366](traefik/traefik#13366) [@​mloiseleur](https://github.com/mloiseleur)) - **\[middleware, authentication, k8s/ingress-nginx]** Clarify intentional auth-response-headers gating and absence of stripping incoming X-Forwarded-\* headers ([#​13342](traefik/traefik#13342) [@​rtribotte](https://github.com/rtribotte)) - **\[middleware]** Clarify entryPoint middleware reference format ([#​13364](traefik/traefik#13364) [@​mloiseleur](https://github.com/mloiseleur)) - **\[security]** Add HTTP/2 header memory exhaustion security documentation ([#​13381](traefik/traefik#13381) [@​emilevauge](https://github.com/emilevauge)) - Adds documentations on maxHeaderBytes ([#​13363](traefik/traefik#13363) [@​juliens](https://github.com/juliens)) - Fix inaccuracies in reference documentation ([#​13304](traefik/traefik#13304) [@​sheddy-traefik](https://github.com/sheddy-traefik)) </details> --- ### Configuration 📅 **Schedule**: (UTC) - Branch creation - At any time (no schedule defined) - Automerge - At any time (no schedule defined) 🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied. ♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox. 🔕 **Ignore**: Close this PR and you won't be reminded about this update again. --- - [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check this box --- This PR has been generated by [Mend Renovate](https://github.com/renovatebot/renovate). <!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiI0My4xNTAuMSIsInVwZGF0ZWRJblZlciI6IjQzLjE1MC4xIiwidGFyZ2V0QnJhbmNoIjoibWFpbiIsImxhYmVscyI6W119--> Reviewed-on: https://git.jfreudenberger.de/JuliusFreudenberger/nix-config/pulls/16 Co-authored-by: Renovate Bot <[email protected]> Co-committed-by: Renovate Bot <[email protected]>
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What does this PR do?
Adds a Security section page documenting how to harden Traefik against HTTP/2 header memory exhaustion (the "HTTP/2 Bomb" class: HPACK amplification combined with an HTTP/2 flow-control window stall to pin large amounts of memory and OOM-kill the proxy).
The page documents the two entry point levers, used together:
http.maxHeaderBytes(added in #d270272f5): cap the decoded request header block so an oversized block is rejected before it can be amplified.http2.maxConcurrentStreams: cap the per-connection stream multiplier.It also points to defense in depth (per-source connection / rate limits at a fronting LB, and adequate memory provisioning).
Motivation
Follow-up to a security report on the HTTP/2 Bomb attack class. Traefik relies on Go's net/http HTTP/2 implementation, consistent with the Go team's position (golang/go#79936); the exposure is controllable via existing entry point configuration, so this documents the recommended hardening rather than introducing a code change.
More
This page is also needed on v3.x; a separate PR will target the current release branch.