etcd RBAC bypass allows unauthorized data access via PrevKv/lease attachment in nested transaction Put requestsGHSA-x35m-3gp4-4fh5
NONEGHSA-x35m-3gp4-4fh5 is a none-severity (CVSS 0) CWE-863 vulnerability in go.etcd.io/etcd/v3. A fix is available for go.etcd.io/etcd/v3 — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-x35m-3gp4-4fh5.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
go.etcd.io/etcd/v3🐹go.etcd.io/etcd/v3🐹go.etcd.io/etcdReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Impact
What kind of vulnerability is it? Who is impacted?
A vulnerability in etcd allows read access via PrevKv, or lease attachment in Put requests within transaction operations, to bypass RBAC authorization checks. An authenticated user without sufficient read or lease-related permissions may be able to access unauthorized data or attach leases by invoking transaction operations with these features enabled.
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.
Patches
Has the problem been patched? What versions should users upgrade to?
This vulnerability is patched in the following versions:
- etcd 3.6.11
- etcd 3.5.30
- etcd 3.4.44
Workarounds
Is there a way for users to fix or remediate the vulnerability without upgrading?
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
- require strong client identity at the transport layer, such as mTLS with tightly scoped client certificate distribution
Reporters
Samy Ghannad (@SamyGhannad on Github) reported that read access via PrevKv in a Put request within etcd transactions bypassed RBAC authorization checks. Benjamin Wang (@ahrtr ) further analyzed that lease attachment in a Put request within etcd transactions also bypassed RBAC authorization checks
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | go.etcd.io/etcd/v3 | ≥ 3.6.0&&< 3.6.11 | 3.6.11go get go.etcd.io/etcd/v3@v3.6.11 |
| 🐹Go | go.etcd.io/etcd/v3 | ≥ 3.5.0&&< 3.5.30 | 3.5.30go get go.etcd.io/etcd/v3@v3.5.30 |
| 🐹Go | go.etcd.io/etcd | all versions | 3.4.44go get go.etcd.io/etcd@v3.4.44 |
Affected Products
etcdetcdDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for go.etcd.io/etcd/v3, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update go.etcd.io/etcd/v3 to 3.6.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-x35m-3gp4-4fh5 is resolved across your whole dependency graph.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This flaw in etcd allows an authenticated user without sufficient read or lease-related permissions to bypass RBAC authorization checks when invoking transaction operations that include PrevKv or lease attachment in Put requests. This can lead to unauthorized data disclosure or lease attachment. The flaw is…
For OpenShift Container Platform until an update can be applied, reduce exposure by restricting network access to etcd server ports so only trusted control-plane components can connect and require strong client identity at the transport layer, such as mTLS with tightly scoped client certificate distribution; these measures limit direct access to the etcd data store but do not replace applying the security update.Source: Red Hat security advisory for GHSA-x35m-3gp4-4fh5 (CC BY 4.0)
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Hardened Images | etcd-main-3.7.1-0.1.hum1 | RHSA-2026:44868 |
Frequently Asked Questions
Is GHSA-x35m-3gp4-4fh5 in your dependencies?
Find it across Go, including transitive dependencies.