Kyverno 1.11.0 before 1.19.2 Memory Exhaustion via Notary Signature Decompression
Kyverno 1.11.0 before 1.19.2 is exposed when deployed as an admission controller with image verification enabled. CVSS rates it 8.7 (high), and no vendor severity is given. Fixed in 1.19.2.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- Fixed in 1.19.2
- Who is exposed
- Not reported
Do first: Upgrade to a fixed version: 1.19.2.
- Last modified
- FIRST's estimate of the chance attackers exploit it in the next 30 days, updated daily.What do these mean? →
- 0.34% · 27th percentile
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 26/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Unclear
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
Kyverno from 1.11.0 before 1.19.2 contains an unbounded decompression vulnerability in FetchSignatureBlob that allows attackers to exhaust memory by supplying highly compressed notary signature layers. Attackers who control registry referrers or signatures can publish small gzip layers that decompress beyond maxPayloadSize, causing admission controller OOM kills and denial of service.
cve.now Index
- Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
- Exposure17/25No login or user action needed, reachable over the network without a login · Unknown: Advisories don't say whether default setups are affected
- Reach?/20Unknown. No tracked technology or package matched
- Severity8.7/10CVSS 8.7
- No patch0/5No signal
What would change the score
- Would score about 71 if added to CISA KEV
- Would score about 66 if CISA's SSVC rates exploitation active
- Would score about 31 if advisories confirm default setups are exposed
What to do
Upgrade to a fixed version: 1.19.2.
Timeline
- CVE published
- First seen by cve.now
Affected versions
- kyverno kyverno
From 1.11.0 · fixed in 1.19.2
Evidence 2
- Advisory
- Link
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-122323
Is CVE-2026-122323 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
A crafted Notary signature can make Kyverno's admission controller use excessive memory when it evaluates an image reference that resolves to attacker-controlled registry content. The controller can then be killed for running out of memory (OOM), which denies service to the cluster.Source: github.com, vulncheck.com
Which versions are affected by CVE-2026-122323?
kyverno: from 1.11.0 before 1.19.2.Source: cve.now feed data
Am I affected, and how do I check?
The advisory lists Kyverno 1.11.0 before 1.19.2. The affected setup is Kyverno deployed as an admission controller with image verification enabled for admitted workloads. To check a cluster's version, run kyverno version, and check whether image verification policies are in use. The GHSA advisory gives a narrower range, >= 1.11.0 and <= 1.16.2.Source: github.com, vulncheck.com
How do I fix CVE-2026-122323?
Upgrade Kyverno to 1.19.2, the version the advisory names as the fix. No workaround is listed in the facts.Source: github.com, vulncheck.com