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CVE-2026-122322: Kyverno Security Vulnerability

CVE-2026-122322 explained: high Security Vulnerability in Kyverno. CVSS 8.7. Affected versions, detection, fixes and CTEM priority.

Last updated: Nov 5, 2026

CVSS
8.7 HIGH
EPSS
n/a
CISA KEV
Not listed
CWE
CWE-409

Sources: National Vulnerability Database, CVE.org, CISA KEV, FIRST EPSS

CVE-2026-122322 Overview

Kyverno from 1.11.0 before 1.19.2 contains an unbounded decompression vulnerability in extractStatement that allows remote attackers to exhaust memory by supplying highly compressed attestation layers. Attackers controlling registry referrer artifacts can push gzip predicate layers exceeding maxPayloadSize when decompressed, causing admission controller OOM kills and denial of service.

Critical Impact

Remote, unauthenticated attackers can exploit this Security Vulnerability in Kyverno. The CVSS base score is 8.7 (High).

Affected Products

  • Kyverno: see the vendor advisory for the exact affected versions

Discovery Timeline

  • 2026-11-05: CVE-2026-122322 published to the National Vulnerability Database by disclosure@vulncheck.com
  • 2026-11-05: last updated in the NVD database

Technical Details for CVE-2026-122322

Vulnerability Analysis

CVE-2026-122322 is a Security Vulnerability weakness (CWE-409) in Kyverno. Based on its CVSS vector, the flaw can be reached over the network, needs no login, and needs no user interaction.

With a CVSS base score of 8.7, apply the vendor fix and confirm exposure on internet facing and business critical assets first.

Root Cause

The vendor description states: Kyverno from 1.11.0 before 1.19.2 contains an unbounded decompression vulnerability in extractStatement that allows remote attackers to exhaust memory by supplying highly compressed attestation layers. Attackers controlling registry referrer artifacts can push gzip predicate layers exceeding maxPayloadSize when decompressed, causing admission controller OOM kills and denial of service.

Attack Vector

Based on the CVSS vector, the flaw can be reached over the network, needs no login, and needs no user interaction. Attack complexity is low complexity.

No exploitation in the wild is confirmed by CISA at the time of the last update. Check the references below for any vendor or researcher proof of concept.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Detection Methods for CVE-2026-122322

Detection Strategies

  • Inventory every instance of Kyverno and compare the running version with the affected range above.
  • Check external attack surface scans for internet facing instances of the component.
  • Run an authenticated vulnerability scan once your scanner ships a check for this CVE.

Monitoring Recommendations

  • Forward Kyverno application, access and audit logs to your SIEM for retrospective hunting.
  • Alert on new processes, configuration changes or outbound connections from the affected service.
  • Track the vendor advisory and the CISA KEV catalog for changes in exploitation status.

How to Mitigate CVE-2026-122322

Immediate Actions Required

  • Apply the fixed version of Kyverno named in the vendor advisory.
  • Prioritize internet facing and business critical instances first.
  • Rescan after the change to confirm the exposure is closed.

Patch Information

Use the fixed version listed in the vendor advisory for Kyverno.

Workarounds

  • If patching must wait, restrict network access to the affected service and place it behind authentication or a web application firewall rule.

CWE References

Technical References

This entry is built directly from NVD, CISA KEV and EPSS data. Verify fixed versions in the vendor advisory before you deploy.

Frequently asked questions

CVE-2026-122322 is a high severity Security Vulnerability in Kyverno with a CVSS score of 8.7. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.

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