CVE-2026-26330
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedEnvoy is a high-performance edge/middle/service proxy. Prior to 1.37.1, 1.36.5, 1.35.8, and 1.34.13, At the rate limit filter, if the response phase limit with apply_on_stream_done in the rate limit configuration is enabled and the response phase limit request fails directly, it may crash Envoy. When both the request phase limit and response phase limit are enabled, the safe gRPC client instance will be re-used for both the request phase request and response phase request. But after the request phase request is done, the inner state of the request phase limit request in gRPC client is not cleaned up. When a second limit request is sent at response phase, and the second limit request fails directly, the previous request's inner state may be accessed and result in crash. This vulnerability is fixed in 1.37.1, 1.36.5, 1.35.8, and 1.34.13.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceIn Envoy's rate limit filter, when both request phase and response phase rate limits are enabled with apply_on_stream_done, the gRPC client instance is reused. After the request phase completes, the inner state is not cleaned up. When the response phase limit request is sent and fails directly, the previous request's inner state is accessed, causing a crash due to improper state management in the reused gRPC client.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data< 1.34.13>= 1.35.0, < 1.35.8>= 1.36.0, < 1.36.5= 1.37.0CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Check Envoy versionRun 'envoy --version' or check the Envoy binary versionAffected if The version falls within: < 1.34.13, >= 1.35.0 and < 1.35.8, >= 1.36.0 and < 1.36.5, or exactly 1.37.0
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Verify rate limit filter is enabledReview Envoy configuration files (YAML/JSON) for presence of 'envoy.filters.http.rate_limit' in the http_connection_manager filter chainAffected if The rate limit filter is present in the filter chain
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Confirm request phase rate limit is configuredInspect the rate limit filter configuration for any 'domain' and 'stage' definitions that include 'request_type' or general rate limit descriptors applied to incoming requestsAffected if Request phase rate limits are defined with stage >= 0
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Confirm response phase rate limit is configuredInspect the rate limit filter configuration for response phase limits, specifically look for 'apply_on_stream_done' set to true in the rate limit action definitionsAffected if Response phase rate limits are configured with apply_on_stream_done enabled (set to true)
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Check for gRPC rate limit service configurationInspect the rate limit filter configuration for 'rate_limit_service' referencing a gRPC service, typically 'envoy.service.rate_limit.v3.RateLimitService'Affected if A gRPC-based rate limit service is configured (not local rate limiting)
Envoy is affected if the version is vulnerable AND the rate limit filter is enabled with BOTH request and response phase limits using a gRPC service where response phase has apply_on_stream_done enabled.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped1.34.131.35.81.36.5
Upgrade Envoy to version 1.37.1, 1.36.5, 1.35.8, or 1.34.13 or later. If upgrade is not immediately possible, review rate limit configurations and consider disabling apply_on_stream_done in response phase limits as a temporary measure.
Upgrade to Envoy 1.34.13 (for 1.34.x), 1.35.8 (for 1.35.x), 1.36.5 (for 1.36.x), or 1.37.1 (for 1.37.x)
- Identify the currently deployed Envoy version using 'envoy --version' or checking the deployment manifests
- Determine the appropriate fixed version based on your current branch: for 1.34.x upgrade to 1.34.13, for 1.35.x upgrade to 1.35.8, for 1.36.x upgrade to 1.36.5, for 1.37.x upgrade to 1.37.1
- Obtain the fixed Envoy binary or container image from the official Envoy releases (https://github.com/envoyproxy/envoy/releases)
- Test the upgrade in a staging or non-production environment to verify the fix and check for regressions
- Deploy the upgraded Envoy version to production
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation4.0 h
- Testing3.0 h
- Review / QA1.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2026-26330 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-26330 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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