CVE-2022-31055Network attack vector

Unauthorized challenge access via misapplied IP ranges

Published Jun 13, 2022 · Updated Apr 23, 2025

Improper access control in Google kCTF before 1.6.0 allows remote attackers to reach challenges from unauthorized IP addresses. The kctf_cluster_ip_ranges path updated Cloud Armor, but its yq expressions targeted generic manifest fields and failed to write ALLOWED_IPS into the manager Deployment. The flaw affects GCE clusters that rely on source-IP ranges; addresses outside the configured allowlist can reach exposed challenges.

CVSS severity7.5
High
EPSS probability0.62%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Improper access control in Google kCTF before 1.6.0 allows remote attackers to reach challenges from unauthorized IP addresses. The kctf_cluster_ip_ranges path updated Cloud Armor, but its yq expressions targeted generic manifest fields and failed to write ALLOWED_IPS into the manager Deployment. The flaw affects GCE clusters that rely on source-IP ranges; addresses outside the configured allowlist can reach exposed challenges.

The record

CVE
CVE-2022-31055
Published
Jun 13, 2022
Updated
Apr 23, 2025
Vendor
Google
Product
kCTF
Classifications
CWE-284, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 13, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 23, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 1.6.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Google · kCTFversion=< 1.6.0

Published CVSS scores

7.5GitHub CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
7.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
5.0NVDAV:N/AC:L/Au:N/C:N/I:P/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-284Improper Access Control
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo