kyverno: Improper Handling of Highly Compressed Data (Data Amplification)
CVE-2026-122322 is a high-severity improper handling of highly compressed data (data amplification) vulnerability in kyverno, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 1.19.2 as the first without the flaw, so updating kyverno to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.4% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update kyverno to 1.19.2 or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by CNA (vulncheck.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.7 | High | CNA (vulncheck.com) |
| CVSS 3.1 | 7.5 | High | CNA (vulncheck.com) |
Official description
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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Handling of Highly Compressed Data (Data Amplification)
The product does not handle or incorrectly handles a compressed input with a very high compression ratio that produces a large output.
More Improper Handling of Highly Compressed Data (Data Amplification) vulnerabilities (CWE-409)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Third-party and government advisories
Other vulnerabilities in kyverno
- 8.8 High severity
- 9.9 Critical severity
- 7.5 High severity
- 9.1 Critical severity
- 7.7 High severity
- 7.5 High severity
Recent Improper Handling of Highly Compressed Data (Data Amplification) vulnerabilities
- 7.5 High severity
- 8.2 High severity
- 8.7 High severity
- 7.5 High severity
- 8.7 High severity
- 7.5 High severity
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