{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","favicon":"https://feed.craftedsignal.io/favicon-32x32.png","feed_url":"https://feed.craftedsignal.io/products/argo-cd-v3.0.0---v3.3.14/feed.json","home_page_url":"https://feed.craftedsignal.io/","icon":"https://feed.craftedsignal.io/apple-touch-icon.png","items":[{"_cs_actors":[],"_cs_cpes":["cpe:2.3:a:argoproj:argo_cd:*:*:*:*:*:*:*:*"],"_cs_cves":[{"cvss":9.9,"id":"CVE-2026-77459"}],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["Argo CD (v2.10.0 - v2.14.21)","Argo CD (v3.0.0 - v3.3.14)","Argo CD (v3.4.0 - v3.4.9)","Argo CD (v3.5.0 - v3.5.3)","Argo CD (v3.6.0-rc1)"],"_cs_severities":["critical"],"_cs_tags":["privilege-escalation","argo-cd","kubernetes","gitops"],"_cs_type":"advisory","_cs_vendors":["Argo Project"],"content_html":"\u003cp\u003eArgo CD contains a security vulnerability (CVE-2026-77459) in how it handles lifecycle hooks during Application deletion. The application-controller skips mandatory AppProject validation checks, including destination namespace restrictions, server constraints, and resource allow/deny lists, when processing PreDelete and PostDelete hooks. Because these hooks are executed with the elevated credentials of the application-controller on the target cluster, an attacker with write access to a synchronized Git repository can define malicious resources that circumvent project-level isolation policies.\u003c/p\u003e\n\u003cp\u003eThis vulnerability affects Argo CD v2.10.0 and all subsequent releases, including the v3.x branch up to recent versions. PreDelete and PostDelete hooks were introduced to extend application lifecycle management, but their implementation lacks the project-context validation applied to standard sync operations. The impact is significant because the application-controller typically possesses broad cluster-level permissions, enabling the creation of unauthorized cluster-scoped objects or resources in restricted namespaces upon application deletion.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAttacker obtains push access to a Git repository synchronized by an Argo CD Application.\u003c/li\u003e\n\u003cli\u003eAttacker modifies the application manifest in Git to include a PreDelete or PostDelete hook (e.g., a Kubernetes Job or ClusterRoleBinding).\u003c/li\u003e\n\u003cli\u003eAttacker defines the hook with metadata that violates the target AppProject's namespace or resource allow/deny lists.\u003c/li\u003e\n\u003cli\u003eArgo CD reconciles the repository and adds the delete finalizer to the Application, marking it as ready for hook execution.\u003c/li\u003e\n\u003cli\u003eAn administrator or automated process triggers the deletion of the target Application.\u003c/li\u003e\n\u003cli\u003eThe application-controller executes the attacker-defined hook using its own elevated credentials, bypassing AppProject validation.\u003c/li\u003e\n\u003cli\u003eThe hook executes malicious code or creates forbidden cluster-scoped objects on the destination cluster.\u003c/li\u003e\n\u003cli\u003eThe attacker achieves unauthorized resource creation or privilege escalation within the destination cluster environment.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eThe vulnerability allows an attacker to bypass multi-tenancy and resource isolation boundaries defined in Argo CD. Successful exploitation enables unauthorized creation of cluster-scoped resources, such as ClusterRoleBindings, or the deployment of arbitrary objects in forbidden namespaces. The number of potentially impacted systems is high, as Argo CD is a widely deployed GitOps controller for Kubernetes environments. If exploited, an attacker could achieve full control over the destination cluster, leading to privilege escalation and potential exfiltration or persistence.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eUpgrade Argo CD to the fixed versions immediately: v3.6.0-rc2, v3.5.4, v3.4.10, or v3.3.15.\u003c/li\u003e\n\u003cli\u003eAudit Git repositories currently synchronized by Argo CD to detect suspicious hook definitions in existing application manifests.\u003c/li\u003e\n\u003cli\u003eImplement the principle of least privilege for the application-controller service account to minimize the blast radius of potential hook-based exploitation.\u003c/li\u003e\n\u003cli\u003eRestrict write access to Git repositories that back Applications deployed within sensitive, high-restriction AppProjects.\u003c/li\u003e\n\u003cli\u003eMonitor application-controller logs for the creation of unauthorized cluster-scoped resources or resources in forbidden namespaces immediately following the deletion of an Application.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-10-15T22:22:59Z","date_published":"2026-10-15T22:22:59Z","id":"https://feed.craftedsignal.io/briefs/2026-10-argo-cd-hooks-bypass/","summary":"Argo CD fails to validate AppProject destination and resource restrictions during PreDelete and PostDelete hook execution, allowing attackers to escalate privileges via the application-controller.","title":"Argo CD AppProject Restriction Bypass via Delete Hooks","url":"https://feed.craftedsignal.io/briefs/2026-10-argo-cd-hooks-bypass/"}],"language":"en","title":"CraftedSignal Threat Feed - Argo CD (V3.0.0 - V3.3.14)","version":"https://jsonfeed.org/version/1.1"}