CVE-2026-33343
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 · uneditedetcd is a distributed key-value store for the data of a distributed system. Prior to versions 3.4.42, 3.5.28, and 3.6.9, an authenticated user with RBAC restricted permissions on key ranges can use nested transactions to bypass all key-level authorization. This allows any authenticated user with direct access to etcd to effectively ignore all key range restrictions, accessing the entire etcd data store. Kubernetes does not rely on etcd’s built-in authentication and authorization. Instead, the API server handles authentication and authorization itself, so typical Kubernetes deployments are not affected. Versions 3.4.42, 3.5.28, and 3.6.9 contain a patch. If upgrading is not immediately possible, reduce exposure by treating the affected RPCs as unauthenticated in practice. Restrict network access to etcd server ports so only trusted components can connect and require strong client identity at the transport layer, such as mTLS with tightly scoped client certificate distribution.
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 etcd versions prior to 3.4.42, 3.5.28, and 3.6.9, an authenticated user with RBAC-restricted key-range permissions can bypass authorization controls by using nested transactions, allowing access to the entire etcd data store regardless of defined permissions.
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< 3.4.42>= 3.5.0, < 3.5.28>= 3.6.0, < 3.6.9CVSS 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
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
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.
-
Determine installed etcd versionRun 'etcd --version' or 'etcdctl version' and note the server version numberAffected if The version is below 3.4.42, or between 3.5.0-3.5.27, or between 3.6.0-3.6.8
-
Verify RBAC authorization is enabledCheck if etcd has users and roles configured by running 'etcdctl user list' and 'etcdctl role list'. If any users or roles exist, RBAC is activeAffected if RBAC is enabled with users and roles defined in etcd
-
Identify users with range-restricted key permissionsRun 'etcdctl role get <rolename>' for each role and check for Range permissions on specific key prefixes. Also run 'etcdctl user get <username>' to see assigned rolesAffected if Any user is assigned a role that has Range permissions limited to specific key ranges rather than full access
You are affected if your etcd version falls within the vulnerable ranges AND you have RBAC enabled with users who have restricted key-range permissions, because such users can bypass those restrictions using nested transactions.
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 · scoped3.4.423.5.283.6.9
Upgrade etcd to version 3.4.42, 3.5.28, or 3.6.9. If immediate upgrade is not feasible, restrict network access to etcd ports and implement mTLS with tightly scoped certificates to reduce exposure.
etcd 3.4.42, 3.5.28, or 3.6.9 (depending on your major version branch)
- 1. Identify your current etcd version by running `etcd --version` or checking the etcd pod/container image tag
- 2. For etcd 3.4.x versions: upgrade to version 3.4.42 or later
- 3. For etcd 3.5.x versions: upgrade to version 3.5.28 or later
- 4. For etcd 3.6.x versions: upgrade to version 3.6.9 or later
- 5. After upgrading, verify RBAC key range restrictions work correctly by testing with a restricted user attempting to access keys outside their permitted range
- 6. If upgrading is not immediately possible, implement network-level mitigations: restrict etcd port (2379/2380) access to trusted clients only, and consider implementing mTLS with tightly scoped client certificates
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation6.0 h
- Implementation12.0 h
- Testing6.0 h
- Review / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $7,968.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-33343 — 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-2026-33343 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
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- 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
- No spam, self-promotion, credentials, or personal data