CVE-2023-48713: Knative.dev/serving Denial of Service Vulnerability

MODERATE
Advisory Identifier: GHSA-qmvj-4qr9-v547
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CVSS 5.3
CWE-400
Published
Advisory Summary

CVE-2023-48713 is a MODERATE (CVSS 5.3) denial of service vulnerability (CWE-400: Uncontrolled Resource Consumption) affecting Knative.dev/serving libraries in the Go ecosystem. The issue involves knative serving vulnerable to attacker-controlled pod causing denial of service of autoscaler. Remediation is available by upgrading affected packages to version 0.39.0.

CVE-2023-48713 at a Glance

CVE Identifier CVE-2023-48713
GHSA Identifier GHSA-qmvj-4qr9-v547
Severity MODERATE
CVSS v3.1 Base Score 5.3
CWE Classification CWE-400: Uncontrolled Resource Consumption
Affected Product Knative.dev/serving
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 5.3

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H).

Attack Vector Network (AV:N)
Attack Complexity High (AC:H)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity None (I:N)
Availability High (A:H)

How to Fix CVE-2023-48713

To remediate this vulnerability, upgrade all affected Knative.dev/serving dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

knative.dev/serving fixed: 0.39.0 
Upgrade knative.dev/serving to 0.39.0
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for knative.dev/serving

How to Check if You Are Affected

To determine whether your application is affected by CVE-2023-48713, inspect your project dependencies for Knative.dev/serving:

inspect dependencies for knative.dev/serving

Analyze the terminal output to locate any version of Knative.dev/serving in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.39.0), 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-400: Uncontrolled Resource Consumption, where the product does not properly control the allocation and maintenance of a limited resource. In Knative.dev/serving, 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

### Summary A vulnerability was fond in Knative Serving that could allow an attacker to crash the Knative Serving autoscaler resulting in a denial of service. The attacker would need to have compromised one pod in the Knative Serving deployment, and with that position they could launch the attack against the autoscaler. When the autoscaler scrapes the metrics of pods, it sends a request to the `/metrics` endpoint of each pod and reads the response. The attacker would need to detect the request from the autoscaler to the `/metrics` endpoint of the pod they had compromised and send a malicious response back to the autoscaler. At this point, the autoscaler would crash. The root cause of the vulnerability was a memory exhaustion issue in the autoscaler that the attacker could trigger with the malicious reponse. The vulnerability would allow a privilege escalation by the attacker from controlling one point to having negative impact on the entire Knative Serving deployment. ### Impact All users are vulnerable to this; Users that have not had any of their pods compromised are not at risk of this vulnerability. ### Mitigation The vulnerability has been patched in v1.10.5, v1.11.3 and v1.12.0 ### Credits The vulnerability was reported by Ada Logics during an ongoing security audit of Knative involving Ada Logics, the Knative maintainers, OSTIF and CNCF.

CVE-2023-48713 Affected Knative.dev/serving Versions

1 component(s)
Fixed Versions:
0.39.0
Product / Package Ecosystem Affected Versions Fixed Version
knative.dev/serving
golang/knative.dev/serving
Go
< 0.39.0
0.39.0

References

GitHub Advisory / Wiki ADVISORY
https://github.com/knative/serving/security/advisories/GHSA-qmvj-4qr9-v547
NVD — CVE-2023-48713 NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-48713
Security Fix Commit FIX COMMIT
https://github.com/knative/serving/commit/012ee2509231b80b7842139bfabc30516d3026ca
Security Fix Commit FIX COMMIT
https://github.com/knative/serving/commit/101f814112b9ca0767f457e7e616b46205551cf1
Security Fix Commit FIX COMMIT
https://github.com/knative/serving/commit/fff40ef7bac9be8380ec3d1c70fc15b57093382a
Knative.dev/serving Source Repository REPOSITORY
https://github.com/knative/serving

Frequently Asked Questions

What is CVE-2023-48713?
CVE-2023-48713 is a security vulnerability in Knative.dev/serving involving Knative Serving vulnerable to attacker-controlled pod causing denial of service of autoscaler under CWE-400: Uncontrolled Resource Consumption.
Which Knative.dev/serving versions are affected?
Affected versions include releases prior to 0.39.0 across affected packages: knative.dev/serving.
What version fixes CVE-2023-48713?
Upgrading to 0.39.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is knative.dev/serving affected?
Yes, knative.dev/serving is affected in releases prior to 0.39.0. Upgrade your dependency to 0.39.0 or later.
What is the CVSS score of CVE-2023-48713?
CVE-2023-48713 has a CVSS v3.1 base score of 5.3 (MODERATE) with vector string CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H.
What CWE is associated with CVE-2023-48713?
CVE-2023-48713 is classified under CWE-400: Uncontrolled Resource Consumption (The product does not properly control the allocation and maintenance of a limited resource.).
How can I check Go dependencies for CVE-2023-48713?
Run the dependency tree command: 'inspect dependencies for knative.dev/serving'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-qmvj-4qr9-v547",
  "modified" : "2023-12-04T15:16:16Z",
  "published" : "2023-11-27T23:27:04Z",
  "aliases" : [ "CVE-2023-48713" ],
  "summary" : "Knative Serving vulnerable to attacker-controlled pod causing denial of service of autoscaler",
  "details" : "### Summary\nA vulnerability was fond in Knative Serving that could allow an attacker to crash the Knative Serving autoscaler resulting in a denial of service. The attacker would need to have compromised one pod in the Knative Serving deployment, and with that position they could launch the attack against the autoscaler. \nWhen the autoscaler scrapes the metrics of pods, it sends a request to the `/metrics` endpoint of each pod and reads the response. The attacker would need to detect the request from the autoscaler to the `/metrics` endpoint of the pod they had compromised and send a malicious response back to the autoscaler. At this point, the autoscaler would crash. The root cause of the vulnerability was a memory exhaustion issue in the autoscaler that the attacker could trigger with the malicious reponse.\n\nThe vulnerability would allow a privilege escalation by the attacker from controlling one point to having negative impact on the entire Knative Serving deployment.\n\n### Impact\nAll users are vulnerable to this; Users that have not had any of their pods compromised are not at risk of this vulnerability.  \n\n### Mitigation\nThe vulnerability has been patched in v1.10.5, v1.11.3 and v1.12.0\n\n### Credits\nThe vulnerability was reported by Ada Logics during an ongoing security audit of Knative involving Ada Logics, the Knative maintainers, OSTIF and CNCF.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "knative.dev/serving"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.39.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/knative/serving/security/advisories/GHSA-qmvj-4qr9-v547"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2023-48713"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/knative/serving/commit/012ee2509231b80b7842139bfabc30516d3026ca"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/knative/serving/commit/101f814112b9ca0767f457e7e616b46205551cf1"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/knative/serving/commit/fff40ef7bac9be8380ec3d1c70fc15b57093382a"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/knative/serving"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-400" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2023-11-27T23:27:04Z",
    "nvd_published_at" : "2023-11-28T04:15:07Z"
  }
}