CVE-2026-73499: etcd: Watch API authorization bypass via open-ended range requests
etcd is a distributed key-value store for the data of a distributed system. Prior to versions 3.5.33, 3.6.14, and 3.7.1, a user granted READ permission on a single exact key can use the Watch gRPC API with clientv3.WithFromKey() to receive watch events for every key lexicographically greater than or equal to the permitted key. In server/etcdserver/api/v3rpc/watch.go, the open-ended RangeEnd sentinel is rewritten before the RBAC permission check in server/auth/rangepermcache.go function isRangeOpPermitted, causing the request to be treated as an exact-key watch. Range/Get and DeleteRange requests are not affected, and the issue affects only clusters with authentication enabled. This issue is fixed in versions 3.5.33, 3.6.14, and 3.7.1.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
etcdto a version that resolves this vulnerability.Fixed in 3.5.33 - Upgrade
Upgrade
etcdto a version that resolves this vulnerability.Fixed in 3.6.14 - Upgrade
Upgrade
etcdto a version that resolves this vulnerability.Fixed in 3.7.1
Event History
Frequently Asked Questions
What is the severity of CVE-2026-73499?
The severity of CVE-2026-73499 is rated at 56.
How do I fix CVE-2026-73499?
To fix CVE-2026-73499, upgrade etcd to versions 3.5.33, 3.6.14, or 3.7.1 or later.
What vulnerability does CVE-2026-73499 address?
CVE-2026-73499 addresses an authorization bypass in the Watch API for etcd.
What systems are affected by CVE-2026-73499?
CVE-2026-73499 affects etcd versions prior to 3.5.33, 3.6.14, and 3.7.1.
What can happen if CVE-2026-73499 is exploited?
If CVE-2026-73499 is exploited, a user with restricted READ permissions could access watch events for unintended keys.