CVE-2023-48312: Github.com/projectcapsule/capsule proxy Authentication Bypass Vulnerability
CRITICALCVE-2023-48312 is a CRITICAL (CVSS 9.8) authentication bypass vulnerability (CWE-287: Improper Authentication) affecting Github.com/projectcapsule/capsule proxy libraries in the Go ecosystem. The issue involves capsule proxy authentication bypass using an empty token. Remediation is available by upgrading affected packages to version 0.4.6.
CVE-2023-48312 at a Glance
Security Impact
CVSS: 9.8
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).
How to Fix CVE-2023-48312
To remediate this vulnerability, upgrade all affected Github.com/projectcapsule/capsule proxy dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
Upgrade github.com/projectcapsule/capsule-proxy to 0.4.6Upgrade github.com/clastix/capsule-proxy to 0.4.6Run the following command in your project directory to verify that all resolved dependencies use the patched release:
inspect dependencies for github.com/projectcapsule/capsule-proxyHow to Check if You Are Affected
To determine whether your application is affected by CVE-2023-48312, inspect your project dependencies for Github.com/projectcapsule/capsule proxy:
inspect dependencies for github.com/projectcapsule/capsule-proxyAnalyze the terminal output to locate any version of Github.com/projectcapsule/capsule proxy in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.4.6), your application is affected.
Note: Verify declared build manifests and deployed runtime container environments.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-287: Improper Authentication, where when an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. In Github.com/projectcapsule/capsule proxy, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2023-48312 Affected Github.com/projectcapsule/capsule proxy Versions
2 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
github.com/projectcapsule/capsule-proxy
|
Go |
< 0.4.6
|
0.4.6
|
|
github.com/clastix/capsule-proxy
|
Go |
< 0.4.6
|
0.4.6
|
References
Frequently Asked Questions
What is CVE-2023-48312?
Which Github.com/projectcapsule/capsule proxy versions are affected?
What version fixes CVE-2023-48312?
Is github.com/projectcapsule/capsule-proxy affected?
Is github.com/clastix/capsule-proxy affected?
What is the CVSS score of CVE-2023-48312?
What CWE is associated with CVE-2023-48312?
How can I check Go dependencies for CVE-2023-48312?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-fpvw-6m5v-hqfp",
"modified" : "2023-11-27T22:07:37Z",
"published" : "2023-11-24T16:53:25Z",
"aliases" : [ "CVE-2023-48312" ],
"summary" : "Capsule Proxy Authentication bypass using an empty token",
"details" : "The privilege escalation is based on a missing check if the user is authenticated based on the `TokenReview` result.\n\nAll the clusters running with the `anonymous-auth` Kubernetes API Server setting disable (set to `false`) are affected since it would be possible to bypass the token review mechanism, interacting with the upper Kubernetes API Server.\n\n# PoC\n\nStart a KinD cluster with the `anonymous-auth` value to `false`. \nIf it is true, it uses anonymous permissions which are very limited by default\n\n```yaml\nkind: Cluster\napiVersion: kind.x-k8s.io/v1alpha4\nnodes:\n- role: control-plane\n kubeadmConfigPatches:\n - |\n kind: ClusterConfiguration\n apiServer:\n extraArgs:\n anonymous-auth: \"false\"\n```\n\nInstall `capsule` and `capsule-proxy`\n\n```\nk port-forward svc/capsule-proxy 9001 \nForwarding from 127.0.0.1:9001 -> 9001\nForwarding from [::1]:9001 -> 9001\nHandling connection for 9001\n```\n\nThen query the proxy\n```\ncurl -g -k -H 'Authorization: Bearer f' -X 'GET' 'https://localhost:9001/api/v1/namespaces'\n```\n\n# Impact\n\nThe whole cluster is exposed to unauthorised users.\n\nThis privilege escalation cannot be exploited if you're relying only on client certificates (SSL/TLS).",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/projectcapsule/capsule-proxy"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "0.4.6"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 0.4.5"
}
}, {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/clastix/capsule-proxy"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "0.4.6"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 0.4.5"
}
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/projectcapsule/capsule-proxy/security/advisories/GHSA-fpvw-6m5v-hqfp"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2023-48312"
}, {
"type" : "WEB",
"url" : "https://github.com/projectcapsule/capsule-proxy/commit/472404f7006a4152e4eec76dee07324dd1e6e823"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/projectcapsule/capsule-proxy"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-287" ],
"severity" : "CRITICAL",
"github_reviewed" : true,
"github_reviewed_at" : "2023-11-24T16:53:25Z",
"nvd_published_at" : "2023-11-24T18:15:07Z"
}
}