{"id":"CVE-2026-122313","kind":"vulnerability","aliases":["CVE-2026-122313"],"related":[],"title":"Kyverno: namespace tenants can modify resources in other namespaces","description":"Kyverno from 1.17.0 before 1.19.2 contains a privilege escalation vulnerability that allows namespace-scoped tenants to modify resources in other namespaces through NamespacedMutatingPolicy targetMatchConstraints.expression CEL output lacking namespace checks. Attackers can emit a literal target such as another tenant's RoleBinding, which the cluster-wide background controller then mutates to add attacker subjects or alter Roles, NetworkPolicies, and ConfigMaps.","summary":"Kyverno versions from 1.17.0 before 1.19.2 let a user limited to one namespace make NamespacedMutatingPolicy target resources in other namespaces. An attacker can have the cluster-wide background controller add their own subjects to another tenant's RoleBinding or alter Roles, NetworkPolicies and ConfigMaps.","severity":"critical","cvss":9.9,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["infrastructure","kubernetes","kyverno","multi-tenant"],"not_affected_if":["kyverno-1.19.2-or-later","kyverno-below-1.17.0","single-tenant-cluster"],"how_to_check":"- Check the installed Kyverno version with `kubectl get deployment -n kyverno -o wide` or the chart version in your Helm release.\n- Check whether any `NamespacedMutatingPolicy` resources exist with `kubectl get namespacedmutatingpolicies -A`.","fix":"- Kyverno: move to `1.19.2` or later, per the affected range in the NVD entry.","status":"open","published_at":"2026-11-05T03:17:23+00:00","first_seen_at":"2026-11-05T03:31:41+00:00","triaged_at":"2026-11-05T03:33:03+00:00","updated_at":"2026-11-05T03:33:03+00:00","category":"infrastructure","confidence":0.6,"triage":{"at":"2026-11-05T03:33:03Z","model":"claude-haiku-5-5","output":{"fix":"- Kyverno: move to `1.19.2` or later, per the affected range in the NVD entry.","reach":"internet","title":"Kyverno: namespace tenants can modify resources in other namespaces","impact":"high","summary":"Kyverno versions from 1.17.0 before 1.19.2 let a user limited to one namespace make NamespacedMutatingPolicy target resources in other namespaces. An attacker can have the cluster-wide background controller add their own subjects to another tenant's RoleBinding or alter Roles, NetworkPolicies and ConfigMaps.","audience":"businesses","category":"infrastructure","nicknames":[],"who_cares":["kubernetes","kyverno","multi-tenant"],"confidence":0.6,"fix_status":"available","needs_auth":"yes","worst_case":"cluster-wide controller grants attacker access to other tenants' RBAC","analyst_note":"Confirm the affected range and fixed version against the vendor advisory on github.com and the VulnCheck entry; the sources here state only the 1.19.2 boundary.","how_to_check":"- Check the installed Kyverno version with `kubectl get deployment -n kyverno -o wide` or the chart version in your Helm release.\n- Check whether any `NamespacedMutatingPolicy` resources exist with `kubectl get namespacedmutatingpolicies -A`.","plain_action":"","needs_analyst":true,"not_affected_if":["single-tenant-cluster","kyverno-below-1.17.0","kyverno-1.19.2-or-later"],"who_is_affected":"Clusters running Kyverno from 1.17.0 up to but not including 1.19.2 that use NamespacedMutatingPolicy. The exposure needs a tenant with rights in one namespace who can create policy input, so single-tenant clusters are less exposed. unknown whether the sources list other affected configurations.","user_interaction":"no","needs_special_setup":"yes","severity_if_unknown":"critical"},"cost_usd":0.000777,"input_tokens":4347,"output_tokens":685,"severity_before":"critical"},"analyst_status":null,"analyst_note":null,"search":"'-122313':12A,15A '-2026':11A,14A '1.17.0':25B,69C '1.19.2':27B,71C 'add':52B,119C 'allow':78C 'alter':62B,123C 'anoth':57B,105C 'attack':43B,97C,120C 'background':50B,114C 'cel':92C 'check':96C 'cluster':48B,112C 'cluster-wid':47B,111C 'configmap':66B,127C 'contain':72C 'control':51B,115C 'cve':10A,13A 'emit':99C 'escal':75C 'infrastructur':16B 'kubernet':17B 'kyverno':1A,18B,22B,67C 'lack':94C 'let':28B 'limit':31B 'liter':101C 'make':35B 'modifi':5A,84C 'multi':20B 'multi-ten':19B 'mutat':117C 'namespac':2A,9A,34B,41B,80C,88C,95C 'namespace-scop':79C 'namespacedmutatingpolici':36B,90C 'networkpolici':64B,125C 'one':33B 'output':93C 'privileg':74C 'resourc':6A,38B,85C 'role':63B,124C 'rolebind':60B,108C 'scope':81C 'subject':55B,121C 'target':37B,102C 'targetmatchconstraints.expression':91C 'tenant':3A,21B,58B,82C,106C 'user':30B 'version':23B 'vulner':76C 'wide':49B,113C","nicknames":[],"mitigations":[],"who_affected":"Clusters running Kyverno from 1.17.0 up to but not including 1.19.2 that use NamespacedMutatingPolicy. The exposure needs a tenant with rights in one namespace who can create policy input, so single-tenant clusters are less exposed. unknown whether the sources list other affected configurations.","tier":"B","verified":{},"analyst_revisit_at":null,"fix_status":"available","audience":"businesses","plain_action":null,"pkeys":[],"ptokens":[],"labels":["critical","infrastructure","kubernetes","kyverno","multitenant"],"campaign_type":null,"first_public_at":"2026-10-21T15:48:06+00:00","kev":null,"cvss_vector":"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","cvss_by":"disclosure@vulncheck.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-122313","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-122313","severity":null,"published_at":"2026-11-05T03:17:23+00:00","modified_at":"2026-11-05T03:17:23+00:00","first_seen_at":"2026-11-05T03:31:41+00:00","fetched_at":"2026-11-05T03:31:41+00:00","note":null}],"documents":[{"id":72705,"url":"https://github.com/kyverno/kyverno/security/advisories/GHSA-f96w-622v-rqpq","title":"Vendor advisory: github.com","kind":"vendor","source":"nvd","publisher":"vendor","text":null,"published_at":"2026-10-21T15:48:06+00:00","relation":"advisory","confidence":null,"note":"Vendor advisory: github.com"},{"id":72706,"url":"https://www.vulncheck.com/advisories/kyverno-1.17.0-before-1.19.2-cross-namespace-privilege-escalation-via-namespacedmutatingpolicy","title":"Third-party advisory: www.vulncheck.com","kind":"advisory","source":"nvd","publisher":"research","text":null,"published_at":null,"relation":"advisory","confidence":null,"note":"Third-party advisory: www.vulncheck.com"}],"exploit_sources":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}