CVE-2021-43979 json
Styra Open Policy Agent (OPA) Gatekeeper through 3.7.0 mishandles concurrency, sometimes resulting in incorrect access control.
published 2021-11-17 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-30841
- cvss
- 5.3
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.1%
- EPSS 1.1% chance of exploitation in 30 days, percentile 64%
- public exploits
- 0
- none known
Summary
Styra Open Policy Agent (OPA) Gatekeeper through 3.7.0 mishandles concurrency, sometimes resulting in incorrect access control. The data replication mechanism allows policies to access the Kubernetes cluster state. During data replication, OPA/Gatekeeper does not wait for the replication to finish before processing a request, which might cause inconsistencies between the replicated resources in OPA/Gatekeeper and the resources actually present in the cluster. Inconsistency can later be reflected in a policy bypass. NOTE: the vendor disagrees that this is a vulnerability, because Kubernetes states are only eventually consistent
Patch / fix
Exploit prediction
1.05% chance of exploitation in the next 30 days, higher than 64% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:P/A:N |
Classification
- Weakness
-
- CWE-670 Always-Incorrect Control Flow Implementation
References
-
github.com
/open-policy-agent/gatekeeper/releases
patch, third-party-advisory
-
github.com
/hkerma/opa-gatekeeper-concurrency-issue
third-party-advisory
Sources
- CVE List CVE-2021-43979
- NVD CVE-2021-43979
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