nono: Sandbox escape on Linux via D-Bus: `systemd-run --user`

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

nono is software that allows users to run AI agents in a zero-latency sandbox. Prior to version 0.55.0, the nono Landlock/seccomp policies allow access to local Unix domain sockets (concrete and abstract). This allows an easy sandbox escape by talking to the per-user systemd dbus socket. Version 0.55.0 patches the issue.

Source published

20 Jul 2026 21:46:32 UTC

Source modified

21 Jul 2026 12:56:44 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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CVSS 3.1 · 6.1 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L

nono is software that allows users to run AI agents in a zero-latency sandbox. Prior to version 0.55.0, the nono Landlock/seccomp policies allow access to local Unix domain sockets (concrete and abstract). This allows an easy sandbox escape by talking to the per-user systemd dbus socket. Version 0.55.0 patches the issue.

Source published

20 Jul 2026 22:17:14 UTC

Source modified

24 Oct 2026 20:10:00 UTC

Observed here

25 Oct 2026 12:17:20 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · [email protected] · Secondary · 6.1 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L

### Summary The nono Landlock/seccomp policies allow access to local Unix domain sockets (concrete and abstract). This allows an easy sandbox escape by talking to the per-user systemd dbus socket. Threat scenario: Running Aider, Claude Code, OpenCode or similar tools with "allow bash" policy so that it can invoke arbitrary host tools like `make`, `gcc`, etc. to write code. ### Reproducer Here, instead of running a tool like `opencode` or `claude` one can just invoke `systemd-run`, but this is something an agent could be tricked into doing: ```bash $ cd ~/src/myproject $ nono run -s --allow-cwd --profile claude-code -- \ systemd-run --user -q --wait --collect \ /bin/sh -c "echo oops > ~/Documents/escaped.txt" $ cat /var/home/test/Documents/escaped.txt oops $ ``` ### Impact Complete sandbox escape. The unsandboxed sibling process can write anywhere the user can write, spawn arbitrary processes with network access, etc. ### Maintainer Context This issue allows a process running inside the sandbox to escape confinement by interacting with local user-scoped IPC mechanisms and regain the authority already held by the invoking user or service account. The issue impacts the sandbox’s confinement and blast-radius reduction guarantees for agents and sandboxed tooling. However, exploitation does not provide privilege escalation, cross-user access, or host compromise beyond the permissions already available to the launcher outside the sandbox. This issue affects the CLI policy layer and bundled sandbox profiles. The underlying core library `nono` does not ship with policy definitions or agent-facing confinement profiles by default, nor do the language SDKs. This is considered a serious issue because an AI agent or untrusted command stream operating within the sandbox could abuse the bypass to perform unauthorized or destructive actions using the delegated authority of the launching user. The root cause was incomplete mediation of local Unix domain socket access within affected sandbox policies. Support for restricting this behavior has since been added and the fix is available in the repository pending release. CVSS rationale: exploitation requires execution within a locally launched sandboxed process using the authority already delegated by the invoking user or service account (`AV:L/PR:L`). The issue allows reliable bypass of sandbox confinement and policy guarantees, resulting in high integrity impact (`I:H`) and limited availability impact (`A:L`) through destructive actions within the launcher’s existing permissions. However, the issue does not provide privilege escalation, cross-user access, or a change in security scope (`S:U`).

Source published

28 May 2026 19:55:40 UTC

Source modified

28 May 2026 20:11:28 UTC

Observed here

24 Oct 2026 13:19:54 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L

Publisher rating · MODERATE