LinkerdApplication
CVE-2025-43915
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 · uneditedIn Linkerd edge releases before edge-25.2.1, and Buoyant Enterprise for Linkerd releases 2.13.0–2.13.7, 2.14.0–2.14.10, 2.15.0–2.15.7, 2.16.0–2.16.4, and 2.17.0–2.17.1, resource exhaustion can occur for Linkerd proxy metrics.
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 affected Linkerd versions, the proxy metrics collection endpoint can be triggered in a way that causes resource exhaustion, potentially leading to denial of service. The vulnerability stems from unbounded or inefficient metric aggregation that can be exploited by repeated requests to the metrics endpoint.
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
LinkerdApplication
< 25.2.1>= 2.13.0, <= 2.13.7>= 2.14.0, <= 2.14.10>= 2.15.0, <= 2.15.7>= 2.16.0, < 2.16.5>= 2.17.0, < 2.17.2CVSS 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
- High
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- Low
- Availability
- High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/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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Identify installed Linkerd versionRun `linkerd version` to retrieve the CLI version, or inspect the Linkerd control plane pods/container images to determine the deployed versionAffected if The version is below 25.2.1 for Linkerd, or between 2.13.0-2.13.7, 2.14.0-2.14.10, 2.15.0-2.15.7, 2.16.0-2.16.4, or 2.17.0-2.17.1 for Buoyant Enterprise for Linkerd
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Locate the proxy metrics endpointIdentify whether the Linkerd proxy metrics endpoint (default port 4191 or the control plane metrics endpoint) is exposed via a service or ingress, and check if it accepts external trafficAffected if The metrics endpoint is reachable from untrusted networks or the internet without authentication
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Verify access controls on metrics endpointReview any existing network policies, service mesh permissions, or proxy configurations that control access to the metrics endpoint. Check if the endpoint requires authentication or is open to all workloadsAffected if No authentication, authorization, or network-level restrictions are configured for the metrics endpoint
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Check for rate limiting configurationInspect Linkerd proxy configuration (via `linkerd inject` annotations or service mesh policies) for any rate limit settings applied to the metrics endpoint pathAffected if No rate limiting is enforced on requests to the metrics endpoint
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Monitor for anomalous metrics trafficReview access logs or network flow data for repeated or high-frequency requests to the metrics endpoint from any single sourceAffected if There is a pattern of repeated requests to the metrics endpoint indicating potential exploitation attempts
The environment is affected if the deployed Linkerd version falls within any of the affected version ranges AND the metrics endpoint is accessible without adequate rate limiting or access controls.
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 · scoped2.16.52.17.225.2.1
Upgrade Linkerd to edge-25.2.1 or later, or upgrade to patched Buoyant Enterprise for Linkerd versions beyond 2.13.7, 2.14.10, 2.15.7, 2.16.4, or 2.17.1. Prior to upgrade, schedule a maintenance window and document current configuration.
Linkerd edge-25.2.1+ | Buoyant Enterprise for Linkerd 2.13.8+, 2.14.11+, 2.15.8+, 2.16.5+, or 2.17.2+
- 1. Identify the currently deployed Linkerd or Buoyant Enterprise for Linkerd version using 'linkerd version' or checking your deployment manifests
- 2. For Linkerd edge releases: Upgrade to edge-25.2.1 or later edge release
- 3. For Buoyant Enterprise for Linkerd 2.13.x: Upgrade to version 2.13.8 or later
- 4. For Buoyant Enterprise for Linkerd 2.14.x: Upgrade to version 2.14.11 or later
- 5. For Buoyant Enterprise for Linkerd 2.15.x: Upgrade to version 2.15.8 or later
- 6. For Buoyant Enterprise for Linkerd 2.16.x: Upgrade to version 2.16.5 or later
- 7. For Buoyant Enterprise for Linkerd 2.17.x: Upgrade to version 2.17.2 or later
- 8. Verify the upgrade was successful by running 'linkerd version' and confirming the proxy metrics endpoint is accessible without excessive resource consumption
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Linkerd
Scoped from the published advisory
- Consultation4.0 h
- Implementation3.0 h
- Testing4.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,680.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2025-43915 — 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-2025-43915 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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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
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