Cyber Resilience

CVE-2026-22039

SSRF in Kyverno ≤ 1.15.3

Public PoCSSRF
Published
27 January 2026
Modified
02 February 2026
Patch / advisory
CVSS Score v3.1 9.9
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.0052 41th percentile
Risk Priority 68 floored blend · peak EPSS

Summary

CVE-2026-22039 is a critical-severity Improper Privilege Management (CWE-269) vulnerability in Kyverno Kyverno. Its CVSS base score is 9.9 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Abuse Elevation Control Mechanism (T1548); ranked at the 41th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to AC-2 (Account Management) and AC-24 (Access Control Decisions) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-22039 is a critical authorization boundary bypass vulnerability in the namespaced Kyverno Policy apiCall feature of Kyverno, a policy engine for cloud native platform engineering teams. It affects Kyverno versions prior to 1.16.3 and 1.15.3. The issue arises because the resolved `urlPath` is executed using the Kyverno admission controller ServiceAccount without enforcement limiting requests to the policy's namespace. This allows control of the `urlPath` through context variable substitution, enabling Kyverno to perform Kubernetes API requests targeting any API path permitted by the ServiceAccount's RBAC. The vulnerability is rated 9.9 on the CVSS 3.1 scale (AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H) and is associated with CWE-269 (Improper Privilege Management) and CWE-918 (Server-Side Request Forgery).

Any authenticated user with permission to create a namespaced Policy can exploit this vulnerability. By crafting a Policy that substitutes variables into the `urlPath`, the attacker causes Kyverno to issue Kubernetes API requests using the elevated privileges of the admission controller ServiceAccount. This breaks namespace isolation, allowing cross-namespace reads such as ConfigMaps and Secrets (where permitted by RBAC), as well as cluster-scoped or cross-namespace writes, for example creating ClusterPolicies.

Kyverno versions 1.16.3 and 1.15.3 address the vulnerability with patches, as detailed in the GitHub security advisory GHSA-8p9x-46gm-qfx2 and specific commits e0ba4de4f1e0ca325066d5095db51aec45b1407b and eba60fa856c781bcb9c3be066061a3df03ae4e3e. Security practitioners should upgrade to these fixed versions to mitigate the risk.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Kyverno is a policy engine designed for cloud native platform engineering teams. Versions prior to 1.16.3 and 1.15.3 have a critical authorization boundary bypass in namespaced Kyverno Policy apiCall. The resolved `urlPath` is executed using the Kyverno admission controller ServiceAccount,…

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with no enforcement that the request is limited to the policy’s namespace. As a result, any authenticated user with permission to create a namespaced Policy can cause Kyverno to perform Kubernetes API requests using Kyverno’s admission controller identity, targeting any API path allowed by that ServiceAccount’s RBAC. This breaks namespace isolation by enabling cross-namespace reads (for example, ConfigMaps and, where permitted, Secrets) and allows cluster-scoped or cross-namespace writes (for example, creating ClusterPolicies) by controlling the urlPath through context variable substitution. Versions 1.16.3 and 1.15.3 contain a patch for the vulnerability.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1548 Abuse Elevation Control Mechanism Privilege Escalation
Adversaries may circumvent mechanisms designed to control privilege elevation to gain higher-level permissions.
T1134 Access Token Manipulation Stealth
Adversaries may modify access tokens to operate under a different user or system security context to perform actions and bypass access controls.
T1548.001 Setuid and Setgid Privilege Escalation
An adversary may abuse configurations where an application has the setuid or setgid bits set in order to get code running in a different (and possibly more privileged) user’s context.
T1548.003 Sudo and Sudo Caching Privilege Escalation
Adversaries may perform sudo caching and/or use the sudoers file to elevate privileges.
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1078 Valid Accounts Stealth
Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-4789Same product: Kyverno Kyverno
CVE-2026-41323Same product: Kyverno Kyverno
CVE-2026-41068Same product: Kyverno Kyverno
CVE-2025-29778Same product: Kyverno Kyverno
CVE-2025-46342Same product: Kyverno Kyverno
CVE-2025-47281Same product: Kyverno Kyverno
CVE-2023-47630Same product: Kyverno Kyverno
CVE-2026-23881Same product: Kyverno Kyverno
CVE-2026-40868Same product: Kyverno Kyverno
CVE-2026-41485Same product: Kyverno Kyverno

Affected Assets

kyverno
kyverno
≤ 1.15.3 · 1.16.0 — 1.16.3

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 5 hardening rules · 5 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V1.3.6
  • V1.5.3
  • V5.3.2
  • V10.4.7

Mitigating Controls (NIST 800-53 r5) AI

Account management directly governs assignment and tracking of privileges so proper implementation stops the weakness from being introduced.

Requiring explicit access-control decisions ensures privileges are evaluated rather than assumed or omitted.

Access enforcement applies the correct privilege checks at every request, structurally preventing unintended spheres of control.

Information flow enforcement can restrict which destinations the server is allowed to contact on behalf of users.

Separation of duties constrains how privileges may be assigned, reducing the chance of overly broad actor control.

Least privilege is the direct countermeasure to improper privilege management; implementing it eliminates the root cause.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-05 mostly match
prevents

PR.AA-05 enforces least privilege/SoD and periodic reviews that directly remove most privilege-assignment defects, yet CWE-269 also covers escalation paths and role design outside a single access-management control.

PR.PS-06 mostly match
prevents

Secure development practices directly include input validation and destination allow-listing that prevent SSRF.

DE.CM-09 partial match
prevents

Runtime monitoring of web applications and services can detect anomalous outbound requests indicative of SSRF.

ID.RA-01 partial match
prevents

Vulnerability identification processes can discover and record SSRF flaws in web applications.

PR.AA-01 partial match
prevents

PR.AA-01 supplies credential/identity lifecycle support that can reduce some privilege-assignment errors but does not itself assign, modify, or check privileges, leaving most of CWE-269's risk unaddressed.

PR.IR-01 partial match
prevents

Network segmentation and egress controls can limit the damage from successful SSRF requests.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Requiring owner approval, segregation of duties, and periodic reviews prevents the assignment of excessive or unnecessary privileges to users or processes.

prevents

Enforcing minimum-necessary privileges, temporary grants, and separation of administrative versus normal identities prevents the over-assignment of rights that CWE-269 describes.

prevents

Dynamic techniques that grant the minimum necessary rights for a given time window and revoke them afterward reduce the window in which excessive or unnecessary privileges can be exploited.

prevents

Explicit restrictions on privileged access and segregation of duties limit the scope of privileges that can be assigned, reducing the chance that excessive or unnecessary privileges are granted to entities.

prevents

Defining and communicating authorization levels for each role limits the assignment of excessive or unnecessary privileges.

mitigates

Separating duties such as developing software from administering production systems prevents any one person from accumulating excessive privileges that would constitute improper privilege management.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Windows 10 (1 rule)
  • V-220712 Only accounts responsible for the administration of a system must have Administrator rights on the system. prevents CWE-269
Windows 11 (1 rule)
  • V-253269 Only accounts responsible for the administration of a system must have Administrator rights on the system. prevents CWE-269
Windows Server 2016 (1 rule)
  • V-225007 Only administrators responsible for the member server or standalone or nondomain-joined system must have Administrator rights on the system. prevents CWE-269
Windows Server 2019 (1 rule)
  • V-205746 Windows Server 2019 must only allow Administrators responsible for the member server or standalone or nondomain-joined system to have Administrator rights on the system. prevents CWE-269
Windows Server 2022 (1 rule)
  • V-254428 Windows Server 2022 must only allow administrators responsible for the member server or standalone or nondomain-joined system to have Administrator rights on the system. prevents CWE-269

References