5.3
MEDIUM
CVE-2021-43979
Styra Open Policy Agent (OPA) Gatekeeper Concurrency Access Control Inconsistency
Description

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

INFO

Published Date :

Nov. 17, 2021, 7:15 p.m.

Last Modified :

Nov. 21, 2024, 6:30 a.m.

Remotely Exploitable :

Yes !

Impact Score :

1.4

Exploitability Score :

3.9
Affected Products

The following products are affected by CVE-2021-43979 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Openpolicyagent gatekeeper
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-43979.

URL Resource
https://github.com/hkerma/opa-gatekeeper-concurrency-issue Third Party Advisory
https://github.com/open-policy-agent/gatekeeper/releases Patch Third Party Advisory
https://github.com/hkerma/opa-gatekeeper-concurrency-issue Third Party Advisory
https://github.com/open-policy-agent/gatekeeper/releases Patch Third Party Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-43979 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-43979 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference https://github.com/hkerma/opa-gatekeeper-concurrency-issue
    Added Reference https://github.com/open-policy-agent/gatekeeper/releases
  • CVE Modified by [email protected]

    Aug. 04, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    May. 17, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    Apr. 11, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    Mar. 21, 2024

    Action Type Old Value New Value
    Added Tag MITRE disputed
  • CVE Modified by [email protected]

    Nov. 07, 2023

    Action Type Old Value New Value
    Changed Description ** DISPUTED ** 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. 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
  • CWE Remap by [email protected]

    Jul. 12, 2022

    Action Type Old Value New Value
    Changed CWE CWE-755 CWE-670
  • Initial Analysis by [email protected]

    Nov. 22, 2021

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:N/AC:L/Au:N/C:N/I:P/A:N)
    Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
    Changed Reference Type https://github.com/hkerma/opa-gatekeeper-concurrency-issue No Types Assigned https://github.com/hkerma/opa-gatekeeper-concurrency-issue Third Party Advisory
    Changed Reference Type https://github.com/open-policy-agent/gatekeeper/releases No Types Assigned https://github.com/open-policy-agent/gatekeeper/releases Patch, Third Party Advisory
    Added CWE NIST CWE-755
    Added CPE Configuration OR *cpe:2.3:a:openpolicyagent:gatekeeper:*:*:*:*:*:*:*:* versions up to (including) 3.7.0
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-43979 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-43979 weaknesses.

Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.07 }} -0.03%

score

0.30870

percentile

CVSS31 - Vulnerability Scoring System
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