CVE-2026-39860: Nixos Nix Security Vulnerability (CVSS 9)

Flatpak is a Linux application sandboxing and distribution framework. Prior to 1.16.4, the Flatpak portal accepts paths in the sandbox-expose options which can be app-controlled symlinks pointing at arbitrary paths. Flatpak run mounts the resolved host path in the sandbox. This gives apps access to all host files and can be used as a primitive to gain code execution in the host context. This vulnerability is fixed in 1.16.4.

Open Neural Network Exchange (ONNX) is an open standard for machine learning interoperability. Prior to version 1.21.0, a path traversal vulnerability via symlink allows to read arbitrary files outside model or user-provided directory. This issue has been patched in version 1.21.0.

LiquidJS is a Shopify / GitHub Pages compatible template engine in pure JavaScript. Prior to 10.25.3, for {% include %}, {% render %}, and {% layout %}, LiquidJS checks whether the candidate path is inside the configured partials or layouts roots before reading it. That check is path-based, not realpath-based. Because of that, a file like partials/link.liquid passes the directory containment check as long as its pathname is under the allowed root. If link.liquid is actually a symlink to a file outside the allowed root, the filesystem follows the symlink when the file is opened and LiquidJS renders the external target. So the restriction is applied to the path string that was requested, not to the file that is actually read. This matters in environments where an attacker can place templates or otherwise influence files under a trusted template root, including uploaded themes, extracted archives, mounted content, or repository-controlled template trees. This vulnerability is fixed in 10.25.3.

Kata Containers is an open source project focusing on a standard implementation of lightweight Virtual Machines (VMs) that perform like containers. From v3.4.0 to v3.28.0, an oversight in the CopyFile policy (and perhaps the CopyFile handler) allows untrusted hosts to write to arbitrary locations inside the guest workload image. This can be used to overwrite binaries inside the guest and exfiltrate data from containers; even those running inside CVMs. This vulnerability is fixed in v3.29.0.

Claude Code is an agentic coding tool. Prior to version 2.1.64, Claude Code's sandbox did not prevent sandboxed processes from creating symlinks pointing to locations outside the workspace. When Claude Code subsequently wrote to a path within such a symlink, its unsandboxed process followed the symlink and wrote to the target location outside the workspace without prompting the user for confirmation. This allowed a sandbox escape where neither the sandboxed command nor the unsandboxed app could independently write outside the workspace, but their combination could write to arbitrary locations, potentially leading to code execution outside the sandbox. Reliably exploiting this required the ability to add untrusted content into a Claude Code context window to trigger sandboxed code execution via prompt injection. Users on standard Claude Code auto-update have received this fix automatically. Users performing manual updates are advised to update to version 2.1.64 or later.

Moby is an open source container framework. In Docker Engine prior to version 29.5.1, Docker Daemon versions 28.5.2 and prior, and Moby Daemon prior to version 2.0.0-beta.14, a race condition during docker cp mount setup allows a malicious container to redirect a bind mount target to an arbitrary host path, potentially overwriting host files or causing denial of service. This issue has been patched in Docker Engine version 29.5.1 and Moby Daemon version 2.0.0-beta.14.