etcd: Watch API authorization bypass via open-ended range requests
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.1epss 0.7%
exploitation probability
0.7%top 50% of all CVEs
observed exploitation
nono source reports it
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/range_perm_cache.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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
Affected products
etcd-io · etcdReferences
https://github.com/etcd-io/etcd/commit/6643f80602461a6095c9b294b6512fd9719bef41https://github.com/etcd-io/etcd/commit/7cf71ec9e2ec54230a5454392fa4ffd4574b41edhttps://github.com/etcd-io/etcd/commit/afeaa624da19085b47fb5ccc7c22a8c421bc2eaehttps://github.com/etcd-io/etcd/commit/e863b001bbf3367003a543aa3099db9892134cd7https://github.com/etcd-io/etcd/releases/tag/v3.5.33https://github.com/etcd-io/etcd/releases/tag/v3.6.14https://github.com/etcd-io/etcd/releases/tag/v3.7.1https://github.com/etcd-io/etcd/security/advisories/GHSA-xg4h-6gfc-h4m8