CVE-2026-124440 json
Kyverno 1.19.1 Privilege Escalation via apiCall Namespace Clamp Bypass
published 20d ago modified 2d ago also EUVD-2026-119560 , GHSA-39w8-hv5g-f73w
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository kyverno/kyverno. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 9.9
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 46%
- public exploits
- 0
- none known
Summary
Kyverno from 1.19.1 before 1.19.2 contains an authorization bypass vulnerability in the apiCall namespace clamp that allows namespace tenants to issue cross-namespace and cluster-scoped API requests by appending malformed percent-escapes to urlPath. Attackers can create namespaced Policies whose apiCall runs as the admission-controller ServiceAccount to read other namespaces' resources and create mutating webhooks, escalating to cluster admin.
Patch / fix
- kyverno kyverno 1.19.2
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 2d ago
Exploit prediction
0.55% chance of exploitation in the next 30 days, higher than 46% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 9.4 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H |
| CNA | 3.1 | 9.9 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
| CNA | 4.0 | 9.4 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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 |
Affected products
- kyverno kyverno
Classification
- Weakness
-
- CWE-441 Unintended Proxy or Intermediary
References
-
github.com
/kyverno/kyverno/security/advisories/GHSA-39w8-hv5g-f73w
vendor-advisory, advisory
-
vulncheck.com
/advisories/kyverno-1.19.1-privilege-escalation-via-apicall-namespace-clamp-bypass
third-party-advisory
Sources
- CVE List CVE-2026-124440
- NVD CVE-2026-124440
- Maintainer advisory GHSA-39w8-hv5g-f73w
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of kyverno/kyverno published their own advisory on GitHub. Reviewed sources take precedence over it.