Kyverno 1.16.0 before 1.19.2 Path Traversal in Namespaced CEL Policies via resource argument
Affects Kyverno 1.16.0 before 1.19.2, where namespaced CEL policies can escape their namespace. 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
- Specific setups only
Do first: Check whether your setup matches what the bug needs. Kyverno version 1.16.0 through before 1.19.2 (affected versions <= 1.19.0 per GitHub advisory). Attacker must be able to create a NamespacedValidatingPolicy in their own namespace.
- Last modified
- FIRST's estimate of the chance attackers exploit it in the next 30 days, updated daily.What do these mean? →
- 0.45% · 39th 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? →
- 17/100 · 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? →
- Specific setups only
- 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, a Kubernetes policy engine, is affected by a path traversal flaw in namespaced CEL policies that lets a tenant with permission to create a NamespacedValidatingPolicy escape its namespace and read and write arbitrary cluster objects using the admission controller's ServiceAccount, which can lead to full cluster takeover. The attacker reaches it over the network with low-privilege login and no user interaction.
Read the original description
Kyverno from 1.16.0 before 1.19.2 fails to validate path segments in the resource argument of resource.get() and resource.post(), allowing namespaced CEL policies to escape their namespace. Tenants who can create a NamespacedValidatingPolicy can insert .. segments to read and write arbitrary cluster objects using the admission controller's ServiceAccount, leading to cluster takeover.
cve.now Index
- Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
- Exposure8/25Specific setups only, reachable over the network
- Reach?/20Unknown. No tracked technology or package matched
- Severity9.4/10CVSS 9.4
- No patch0/5No signal
What would change the score
- Would score about 67 if added to CISA KEV
- Would score about 62 if CISA's SSVC rates exploitation active
- Would score about 24 if CISA's SSVC rates it automatable
What to do
Check whether your setup matches what the bug needs.
Kyverno version 1.16.0 through before 1.19.2 (affected versions <= 1.19.0 per GitHub advisory). Attacker must be able to create a NamespacedValidatingPolicy in their own namespace.Upgrade to a fixed version: 1.19.2.
Timeline
- CVE published
- First seen by cve.now
- Posted on X by cve.now
Affected versions
- kyverno kyverno
From 1.16.0 · 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-2026-122311
Is CVE-2026-122311 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?
Kyverno fails to validate path segments in the resource argument of namespaced CEL policies, which lets a policy escape its own namespace. The advisory says this allows reading and writing arbitrary cluster objects using the Kyverno admission controller's ServiceAccount.Source: vulncheck.com, github.com
Which versions are affected by CVE-2026-122311?
kyverno: from 1.16.0 before 1.19.2.Source: cve.now feed data
Am I affected, and how do I check?
Kyverno versions from 1.16.0 before 1.19.2 are affected. To check a cluster, look at the installed Kyverno version, for example with kubectl get deployment -n kyverno or helm list -n kyverno. The bug concerns namespaced CEL policies (NamespacedValidatingPolicy), and the advisory's prerequisite is the ability to create those policies in a namespace.Source: vulncheck.com, github.com
How do I fix CVE-2026-122311?
Upgrade Kyverno to version 1.19.2 or later, which contains the fix.Source: vulncheck.com, github.com