CVE-2026-33343
No exploitation reported by the sources we read.
- Published2026-03-26
- WeaknessCWE-863
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
etcd 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.
Timeline
dates in UTC- 2026-03-2614:16CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 21:37 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-33343?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-33343?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
OSV · NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 3.3 | ≤ 3.3.27 | no fix published | OSV |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 3.6 | ≥ 3.6.0, < 3.6.9 | 3.6.9 | NVD · OSV |
| 3.6 | ≥ 3.6.0-alpha.0, < 3.6.9 | 3.6.9 | OSV |
| 3.5 | ≥ 3.5.0, < 3.5.28 | 3.5.28 | NVD · OSV |
| 3.5 | ≥ 3.5.0-alpha.0, < 3.5.28 | 3.5.28 | OSV |
| 3.4 | < 3.4.42 | 3.4.42 | NVD · OSV |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
Advisories and patches
- github.comMitigation · Vendor Advisory
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
- Published
- 2026-03-26
- Last Modified
- 2026-06-17
- NVD status
- Analyzed
Frequently asked questions
What is CVE-2026-33343?
Is CVE-2026-33343 actively exploited?
What is the CVSS score for CVE-2026-33343?
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