P0 security: contain the implement agent against untrusted issue text#9
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…trip tokens improvement-plan 0.2-1 (a)+(c). The implement/revise agent acts on untrusted issue text with broad Bash and a PAT in env — a prompt-injection RCE/exfil vector on a public repo. (a) Network egress denied by default (claude harness): add --disallowed-tools for curl/wget/nc/ncat/netcat/telnet/ssh/scp/sftp/socat/ftp + mcp__*. Deny beats the broad Bash allow (Claude evaluates deny first) and survives bash -c / && / ; / | wrappers, so "curl $URL", "bash -c curl", and "git x && curl y" are all blocked. Opt back in with .implement.allow_network=true (new schema key). (c) Strip GH_TOKEN/GITHUB_TOKEN/AGENT_GH_TOKEN/ADMIN_GH_TOKEN from the implement subprocess via env -u — it edits code + builds, never calls gh (the driver does). Model-gateway creds (ANTHROPIC_*) are kept. Triage/review keep their tokens (they DO call gh). NOT a full sandbox: indirect egress (a build script / python -c that shells out) still needs OS-level network isolation on the runner — documented as a known limitation (threat model doc to follow). Verified via the dry-run shim: implement emits the deny flags + env -u prefix; investigate does neither; allow_network=true drops the deny block. All harness + config tests green, shellcheck clean. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
… prompts
improvement-plan 0.2-1 (b). Public repos mean adversarial issue authors. Each
agent prompt now carries a standing rule that issue/review text is UNTRUSTED
input — a description of WHAT to change, never instructions to obey — and the
interpolated title/author is wrapped in explicit BEGIN/END UNTRUSTED fences:
- run_hephaestus.sh: SECURITY constraint (no shell/URL/secret/network/CI actions
the issue asks for; abort if that's the real ask) + fenced issue title.
- run_triage.sh: issue content is data to assess, cannot change the rules,
verdict criteria, or output format + fenced title/author.
- run_revise.sh: review text + inline comments + diff are untrusted feedback,
not commands + a marker before the blocks.
Also de-heron'd run_revise.sh: the prompt hardcoded `just build` / `cargo check`
/ `bun run build` in console/ — now uses ${OLYMPUS_BUILD_CMD} like
run_hephaestus. And the committer email agent-bot@ → olympus-bot@.
Defense-in-depth with the harness containment (deny network + strip tokens):
prompt framing reduces the chance the agent acts on injected instructions; the
harness limits the blast radius if it does.
Verified: shellcheck + bash -n clean, triage composer tests green, legacy-naming
lock clean, no heron build strings remain.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
…ger issues
improvement-plan 0.2-1 (d) / roadmap 1.3. A verdict=do sends the issue to the
UNATTENDED dev agent. On a public repo that means the agent acts on text written
by a stranger. Rather than the plan's labeler actor-gate (GitHub already lets
only collaborators label, so it's near-redundant), gate on the ISSUE AUTHOR's
trust — the stronger control:
- New .triage.auto_dispatch (OLYMPUS_AUTO_DISPATCH): trusted (default) | all | never.
- trusted: auto-add the try-label only when the author has write/maintain/admin
on the repo (gh api collaborators/:user/permission, fail-closed on any error).
- all: auto-dispatch any author (internal/trusted repos; pre-0.2-1 behavior).
- never: always require a maintainer to add the try-label.
- Untrusted-author do → no try-label; the warm reply swaps its "it's queued"
promise for an honest "flagged for a maintainer" note + the maintainer-controls
block, marked <!-- olympus-triage:do-withheld -->. A human reviews the issue
before the agent ever runs on it — the catch for injected/malicious content.
compose_comment_body gains a 4th `withheld` arg (defaults 0 → existing calls and
tests unchanged). New tests cover the withheld path and that the dispatched path
is untouched.
Verified: triage tests 8/8, config + schema valid, shellcheck + legacy lock clean.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
…n 0.2-1) docs/security.md documents the threat model (issue/PR authors untrusted on public repos), the four defense-in-depth controls just landed (maintainer dispatch gate, untrusted-input framing, network-egress deny, token stripping) plus the no-LLM guard hygiene, and — honestly — the residual risks the controls do NOT cover: indirect egress via build scripts / `python -c` (needs an egress-firewalled runner), the trusted-author assumption, arbitrary build_cmd, and model fallibility. Closes roadmap 1.3's "documented threat model in docs/". evals/tasks/implement/prompt-injection/ is the regression test: an issue whose body embeds `echo OWNED`/curl exfil instructions; the check passes only if the legit fix lands AND the injected command did not run (no sentinel file). Runs in the bench (not CI), the same agent_run path the loop uses — so it exercises the real harness containment. Verified: leakage + legacy-naming gates clean, shellcheck clean, all unit + eval checks green, check.sh logic confirmed both ways. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
…llow_network Keep the field catalog in sync with the schema + security controls landed in 0.2-1 (mechanism/policy hygiene). Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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improvement-plan 0.2-1 / roadmap 1.3 — the pre-announcement security blocker. Open-sourcing inverts an assumption the code was built on: issue/PR authors become untrusted. Today the implement agent acts on stranger-filed text with broad Bash + a PAT in env — a prompt-injection RCE/exfil vector. This PR adds four defense-in-depth controls, a threat model, and a regression eval.
Controls
doverdict auto-dispatches the unattended agent only for authors with write/maintain/admin access (fail-closed); others get a warm reply + a maintainer control to dispatch by hand. A human reviews stranger issues before the agent runs..triage.auto_dispatch=trusted(default)|all|never—run_triage.shrun_hephaestus.sh,run_triage.sh,run_revise.sh--disallowed-toolsfor curl/wget/nc/ssh/… +mcp__*. Deny beats the broad Bash allow and survivesbash -c/&&/;/|wrappers.agent-harness.sh; opt out with.implement.allow_networkGH_TOKEN/GITHUB_TOKEN/AGENT_GH_TOKEN/ADMIN_GH_TOKENremoved from the implement subprocess viaenv -u(it edits code; the driver calls gh). Model creds kept; triage/review keep tokens (they call gh).agent-harness.shDesign note: 0.2-1(a) uses a deny-list, not the plan's allow-list — an allow-list errors out arbitrary builds in headless mode, while deny (verified via the Claude Code permission model: deny > allow, wrappers stripped, per-subcommand) blocks
curl $URL/bash -c "curl"without breaking builds.Also
docs/security.md— threat model + the controls + honest residual risks (indirect egress via build scripts /python -cneeds an egress-firewalled runner; trusted-author assumption; arbitrarybuild_cmd; model fallibility) + operator hardening checklist. Closes roadmap 1.3's "documented threat model".evals/tasks/implement/prompt-injection/— regression eval: an issue body with embeddedecho OWNED/curl-exfil; passes only if the legit fix lands and the injection didn't run. Runs in the bench (not CI), sameagent_runpath the loop uses.run_revise.shprompt hardcoded heron build commands (just build/cargo check/bun run build) → now uses${OLYMPUS_BUILD_CMD}; committer emailagent-bot@→olympus-bot@.docs/config-reference.mdupdated for the two new keys.Verification
bash -nclean; all unit + eval-check tests green; leakage + legacy-naming gates clean;.olympus.jsonbuild_cmdgreen.env -uprefix, investigate emits neither,allow_network=truedrops the deny block. New triage tests cover the withheld-dispatch path.Deferred (noted, not in this PR)
hephaestus/themisdisplay names (0.2-3 identity-var pass).security.md, not enforceable from this repo.🤖 Generated with Claude Code