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Full vulnerability report · 2026
CVE-2026-33343High confidence

etcd: Nested etcd transactions bypass RBAC authorization checks

etcd-io · etcd

Official source article: GitHub GHSA-RFX7-8W68-Q57Q ↗. Check the applicable product and release in the original source.

0.0NoneCVSS 3.1
Recommended action
Patch only the product branches with a verified fix

The structured sources do not provide enough evidence for a stronger action window. Track vendor updates and assess local exposure. Verified remediation exists for at least one product or source, but 2 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityNoneOperational priority:None, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
  • EPSS is 0.26% for the current model date.

Compensating controls

  • Apply the linked authoritative mitigation while planning the permanent fix.
  • Restrict the affected network interface to trusted sources where business-safe.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs etcd-io etcd and falls inside the recorded affected range.
  2. Recheck the vendor advisory before scheduling a change because no verified fixed version is currently retained.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: Manual assessmentRemediation target: Manual assessment

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Cross-source reconciliation

Remediation availability differs by product scope

Verified remediation exists for at least one product or source, but 2 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Distribution package intelligence

Release-specific package status

Alpine, Debian, ubuntu findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.

6 package states
Package result overrides the generic status

BlackTree has verified remediation for at least one product or source, but the relevant distribution still reports no fixed package for 2 affected package states shown here. Treat those rows as affected with no fix until that distribution publishes a fixed version.

Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Distribution releaseSource packageVendor stateFixed versionEvidence
Alpine v3.23v3.23 · communityetcdVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.3.6.10-r0Alpine Security Database ↗Source updated 11 Sep 2026
Debian trixietrixie · sourceetcdAffected, no fix publishedDebian currently tracks this release as open.Not published in this feedDebian Security Tracker ↗Source updated 5 Oct 2026
Debian bookwormbookworm · sourceetcdAffected, no fix publishedDebian currently tracks this release as open.Not published in this feedDebian Security Tracker ↗Source updated 5 Oct 2026
Debian forkyforky · sourceetcdVendor fix publishedDebian records a fixed source-package version for this release.3.5.16-11Debian Security Tracker ↗Source updated 5 Oct 2026
Debian sidsid · sourceetcdVendor fix publishedDebian records a fixed source-package version for this release.3.5.16-11Debian Security Tracker ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · esm-appsetcdUnder evaluationCanonical reports that the package might be affected and still needs evaluation or fixing.Not published in this feedCanonical Ubuntu Security ↗Source updated 5 Oct 2026
Open-source package ranges8 source-attributed ranges

These OSV and GitHub advisory ranges apply only to the named package and ecosystem. A listed fixed version is not a universal product patch or proof that an update is installed.

Ecosystem and packageAffected rangeFirst fixed versionEvidence
Gogo.etcd.io/etcdSEMVER: introduced 0; last affected 3.3.27Not statedOSV record ↗aggregator derived · 10 Sep 2026
Gogo.etcd.io/etcd/v3SEMVER: introduced 3.6.0-alpha.0; fixed 3.6.93.6.9OSV record ↗aggregator derived · 10 Sep 2026
Gogo.etcd.io/etcd/v3SEMVER: introduced 3.5.0-alpha.0; fixed 3.5.283.5.28OSV record ↗aggregator derived · 10 Sep 2026
Gogo.etcd.io/etcd/v3SEMVER: introduced 0; fixed 3.4.423.4.42OSV record ↗aggregator derived · 10 Sep 2026
gogo.etcd.io/etcd<= 3.3.27Not statedGitHub advisory ↗upstream repository advisory · 27 Mar 2026
gogo.etcd.io/etcd/v3>= 3.6.0-alpha.0, <= 3.6.83.6.9GitHub advisory ↗upstream repository advisory · 27 Mar 2026
gogo.etcd.io/etcd/v3>= 3.5.0-alpha.0, <= 3.5.273.5.28GitHub advisory ↗upstream repository advisory · 27 Mar 2026
gogo.etcd.io/etcd/v3<= 3.4.413.4.42GitHub advisory ↗upstream repository advisory · 27 Mar 2026
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2026-20077

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionPatch only the product branches with a verified fix

The structured sources do not provide enough evidence for a stronger action window. Track vendor updates and assess local exposure. Verified remediation exists for at least one product or source, but 2 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
01

What, why and how

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.

What

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.

Why

The application performs an authorisation check, but it does not correctly enforce the required permission boundary.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

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.

Why

The application performs an authorisation check, but it does not correctly enforce the required permission boundary.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Incorrect Authorization → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-863 ↗

CWE-863: Incorrect Authorization. The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:N

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.INoneIntegrity impact: No direct loss is represented by this metric.ANoneAvailability impact: No direct loss is represented by this metric.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedCWE-863
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-2026-0818etcd: Mehrere Schwachstellen ermöglichen Umgehen von Sicherheitsvorkehrungen

Ein Angreifer kann eine Schwachstellen in etcd ausnutzen, um Sicherheitsvorkehrungen zu umgehen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20260401Security Bulletin 01 Apr 2026

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 01 Apr 2026, published on 1 April 2026. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0376Multiples vulnérabilités dans les produits Microsoft

Bulletin de sécurité Microsoft CVE-2026-27651 du 27 mars 2026 Bulletin de sécurité Microsoft CVE-2026-27654 du 27 mars 2026 Bulletin de sécurité Microsoft CVE-2026-27784 du 27 mars 2026 Bulletin de sécurité Microsoft CVE-2026-28753 du 27 mars 2026 Bulletin de sécurité Microsoft CVE-2026-28755 du 27 mars 2026 Bulletin de sécurité Microsoft CVE-2026-32647 du 27 mars 2026 Bulletin de sécurité Microsoft CVE-2026-32748 du 27 mars 2026 Bulletin de sécurité Microsoft CVE-2026-33515 du 27 mars 2026 Bulletin de sécurité Microsoft CVE-2026-33526 du 27 mars 2026 Bulletin de sécurité Microsoft CVE-2026-4645 du 27 mars 2026 Bulletin de sécurité Microsoft CVE-2026-33343 du 28 mars 2026 Bulletin de sécurité Microsoft CVE-2026-33413 du 28 mars 2026 Une gestion de version détaillée se trouve à la fin de ce document. Risque Non spécifié par l'éditeur Systèmes affectés azl3 etcd 3.5.21-1 versions antérieures à 3.5.28-1 azl3 glibc 2.38-18 versions antérieures à 2.38-19 azl3 kernel 6.6.126.1-1 versions antérieures à 6.6.130.1-1 azl3 libsoup 3.4.4-12 versions antérieures à 3.4.4-14 azl3 ncurses 6.4-2 versions antérieures à 6.4-3 azl3 nginx 1.28.2-1 versions antérieures à 1.28.3-1 azl3 python-pyasn1 0.4.8-1 versions antérieures à 0.4.8-2 azl3 squid 6.13-3 versions antérieures à 6.13-4 cbl2 ncurses 6.4-3 versions ant

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2026-009258etcd-ioのetcdにおける不正な認証に関する脆弱性

etcdは分散システムのデータを管理する分散型キー・バリューストアです。バージョン3.4.42、3.5.28、および3.6.9より前のバージョンでは、RBACでキー範囲の権限が制限された認証済みユーザーがネストされたトランザクションを使用してすべてのキー単位の認可を回避できました。これにより、etcdへの直接アクセス権を持つ任意の認証済みユーザーがキー範囲の制限を事実上無視してetcdの全データストアにアクセス可能となります。Kubernetesはetcdの組み込み認証および認可に依存せず、APIサーバーが独自に認証と認可を処理するため、一般的なKubernetesの導入は影響を受けません。バージョン3.4.42、3.5.28、および3.6.9には修正パッチが含まれています。すぐにアップグレードができない場合は、対象のRPCを実質的に認証なしとして扱うことで被害を軽減してください。etcdサーバーポートへのネットワークアクセスを制限し、信頼できるコンポーネントのみが接続可能にして、mTLSや厳密に範囲を絞ったクライアント証明書配布などの強力なクライアント認証をトランスポート層で要求してください。

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Fix availability varies by product
Affected
etcd: >= 3.5.0-alpha.0, < 3.5.28, >= 3.6.0-alpha.0, < 3.6.9, < 3.4.42
Fixed
No fixed version is explicitly recorded in the structured CVE data.
Action
Use the product-specific evidence above. Patch only products with a verified fixed release, and keep every affected or under-investigation state without a matching fix in the remediation queue.
Workaround
A mitigation or workaround reference is available from the source linked below; validate it against the affected product and version.
04

Evidence and provenance

Published 26 Mar 2026 · Last source change 26 Mar 2026, 18:25 UTC · CWE-863 · Incorrect Authorization

CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2026-20077
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2026-33343 · cve.blacktree.nl