The security pass. Six findings, none reachable by visiting the site and
every one a boundary this codebase says it keeps.
A subagent is pinned to a list of read-only commands, in every mode,
unattended, with no card anybody could approve -- and `find *` was on it.
find writes files with -fprintf, runs programs with -exec and removes them
with -delete, and none of that needs a character the metacharacter guard
refuses. A page the model had just read could ask for a helper and get a
key into authorized_keys, from Plan mode, which promises to change
nothing. Refused in `subject()` rather than trimmed from the list: a
pattern cannot say "and no dangerous flags", and "this one looks
read-only" is exactly what put find there.
The loopback guard missed `0.0.0.0`, which is not is_loopback but does
connect to localhost -- so it answered a *decided* False and skipped the
DNS half too. The one spelling of "this machine" that walked past a guard
whose whole job is that sentence.
Twice in the update helper, which is the one place this deliberately
crosses a privilege boundary: root ran a script the service account owns,
and root sourced a file that account can replace. Either turns a
compromise of the web application into root. The first needed no
compromise at all -- a pull happens as the service user and root runs
whatever it fetched, so control of the branch was control of root. The
old test asserted that exact ExecStart line and had pinned it in place.
Push endpoints skipped check_url, the only outbound request that did. And
a chat could be filed in another account's folder, which hands over its
system prompt -- `_new_chat` resolved the folder, discarded it when it was
not the caller's, and stored the raw id anyway.
An existing helper install keeps the old wiring until install.sh is
re-run; update.sh now says so when it finds itself inside the checkout.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
"Nothing runs on the LLeMbas host" is the sentence the absent sandbox and the
absent local MCP rest on, and an SSH profile aimed at 127.0.0.1 walked straight
past it -- through a real login, with every gate in policy.py still applying,
onto the machine holding the database and the Fernet key. From the SSH layer
down it is indistinguishable from a container on the network, so nothing here
could have noticed.
One switch, three positions: never, one named port, anywhere. The middle one is
the one with a real use -- a container that published its SSH port on the
loopback interface is genuinely somewhere else -- and port 22 is refused even
there, because that one is this host's own sshd.
Enforced in five places, because a row can predate a setting: saving a profile,
`session.resolve` (the control every agent tool, the terminal and the canvas go
through), the composer's picker, browsing, and the draft the panels open against
before a chat exists. Check refuses before it opens its socket rather than after.
And the recognition never resolves a name on the request path. `refusal` runs
several times per page render; the first version of this looked names up inline
and the suite went from two minutes to not finishing. Literal forms are decided
from the string, a name is settled where a network call is already expected, and
the answer lives on the row. The gap that leaves is written down rather than
discovered.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Homer
Jaroslav Beneš