Claude Code 2.1.268 security checklist: patch credential redaction and trust-boundary regressions

Quick answer

Claude Code 2.1.268 fixes two credential-exposure paths and several adjacent trust-boundary regressions. Plugin or marketplace failures could show a token or password embedded in a Git source URL. MCP and plugin detail commands or login errors could show secrets after ${VAR} placeholders were resolved. The same release also fixes a respawned in-process teammate loading tools or a system prompt from a same-named agent file in an untrusted folder, plus deny/ask rules that could miss real paths behind symlinked directories or commands the checker could not analyze.

Upgrade every launcher that can display diagnostics or execute tools, but do not stop at the version check. If a real credential may have appeared in terminal output, shared logs, CI artifacts, support tickets, or screen recordings, revoke and rotate it; redaction in the new build cannot erase copies created earlier. Then run synthetic redaction, workspace-trust, and permission canaries before restoring unattended work.

The release note confirms fixes, not exploitation, a CVE, or a complete affected-version range. Treat 2.1.268 as the first version verified for these named fixes and scope incident response to evidence you actually have.

Who this is for

This guide is for developers and platform teams using private plugin marketplaces, authenticated Git sources, MCP servers with environment-based secrets, in-process teammates, or permission rules on macOS and Linux paths. It also applies to anyone who copies Claude Code diagnostics into tickets or shared chat.

The earlier Claude Code 2.1.234 security checklist covers a different redaction and marketplace-host set. This page focuses on the newly fixed error-output paths and 2.1.268 trust regressions. Keep the 2.1.223 permission-bypass canaries and 2.1.248 restricted-mode boundary as separate controls.

What changed in 2.1.268

Surface	Official fix	What remains your responsibility
Git-backed plugin or marketplace errors	Stop showing a token or password from a Git source URL	Remove embedded credentials where possible, rotate exposed values, and control diagnostic retention
MCP and plugin details or login errors	Stop showing secrets resolved from ${VAR} placeholders	Keep secret values out of repository settings and test every output surface you distribute
Respawned in-process teammates	Do not load a same-named agent file from an untrusted folder	Establish workspace trust before loading project instructions and verify the effective agent definition
Symlinked paths	Apply deny/ask rules when the request uses the real location behind paths such as macOS /tmp or Linux /bin	Test the path spellings present on every supported host
Unanalyzable shell lines	Do not let a Read or Edit deny disappear when env -C, eval, or a similar construct is on the same line	Keep broad shell authority constrained by sandboxing and least privilege
Sandbox messaging	Stop claiming confinement that is not actually enforced	Verify filesystem isolation, network policy, and unsandboxed fallbacks independently

These are separate assertions. A clean plugin error does not prove MCP output is clean; a passing symlink test does not prove an agent file came from a trusted workspace.

Incident-response decision tree

Did a pre-2.1.268 process use authenticated Git URLs or secret-backed MCP config?
  no  -> upgrade, restart, and run the canaries
  yes -> could diagnostics have been retained or shared?
           no evidence of output -> upgrade and inspect local history by metadata only
           output existed         -> stop sharing, identify credential owner and scope
                                   -> revoke or rotate the affected credential
                                   -> remove retained copies where policy permits
                                   -> upgrade every launcher and run the canaries

Do not search broad logs by printing the real secret again. Use known artifact names, timestamps, command classes, access logs, or a secure secret-scanning process that does not echo matched values.

A six-stage rollout

1. Inventory the real launchers

Record the binary behind the terminal, Desktop Code tab, VS Code, CI runner, remote host, and long-running background session. Also list the surfaces that can retain output: terminal scrollback, shell capture, CI logs, telemetry, issue attachments, and screen recordings.

surface / resolved executable / version:
config directory / managed settings source:
plugin marketplace used: yes | no
MCP secret placeholders used: yes | no
diagnostic retention destination / owner / expiry:

Upgrade through the controlled channel you already use, restart long-lived processes, and verify claude --version reports 2.1.268 or newer. A package manifest is not proof that an existing process changed.

2. Triage exposure without replaying it

For each authenticated Git URL or secret-backed MCP server used by an older process, ask four questions:

1. Did an error or detail command run?
2. Was its output captured outside the operator's private terminal?
3. Could the credential authorize a write, package install, repository read, or MCP action?
4. Do provider logs show unexpected use after the output time?

Rotate when the credential was actually rendered, copied, broadly retained, or cannot be ruled out under your incident policy. Do not claim compromise from a version number alone, and do not leave a known exposed write credential active merely because no suspicious access is visible.

3. Run a fake-secret redaction matrix

Create a disposable repository and credentials that are intentionally fake, unique, and useless. Exercise only normal error paths:

• A deliberately unreachable Git-backed marketplace source containing a fake username and fake token.
• An unreachable MCP server whose config references a fake value through ${VAR}.
• /mcp, /plugin, claude mcp list or get, plugin JSON output, and the corresponding login or validation error used in your workflow.

Capture the output locally, search for the exact fake marker, and require zero matches. The output should retain enough non-secret context to identify the failing server or source. Delete the fixture and capture after recording the count, not the marker itself.

4. Prove workspace trust for respawned teammates

Use two disposable folders: one explicitly trusted and one left untrusted. Give each a same-named agent file, but place a harmless, visibly different instruction and tool list in each. Start and respawn an in-process teammate only through the feature your workflow already uses.

Pass when the teammate retains the trusted definition and never acquires the untrusted folder's prompt or tools. Record the trusted root, agent name, definition hash, tool inventory, and respawn result. If you cannot reproduce the teammate lifecycle deterministically, keep that workflow out of unattended promotion rather than treating an untested path as safe.

5. Test symlink and analyzer-denial canaries

Use a harmless file under a temporary directory and a deny or ask rule that should protect it. On macOS, test both /tmp/... and its real /private/tmp/... spelling; on Linux, include only symlink aliases that exist on the canary host. Then test a benign denied Read or Edit on a line that also uses an environment or directory wrapper your automation permits.

Pass only when every equivalent path and wrapper reaches the same deny/ask result and the canary file remains unchanged. This validates permission analysis, not operating-system isolation. Keep sandbox failIfUnavailable behavior, network controls, and unsandboxed retry policy as separate evidence.

6. Promote by surface, with a terminal record

Restore one low-impact workflow on one launcher. Compare the requested action, displayed decision, process exit, file or provider side effect, and terminal state. Expand only after terminal, IDE, CI, and background surfaces each pass the relevant matrix.

Copyable acceptance record

date / owner / host:
surface / executable / claude_version / restarted:
old-version diagnostic event: none | private-only | retained | shared | unknown
credential type / authority / revoked_at / rotated_at:
git_error_fake_marker_matches:
mcp_detail_fake_marker_matches:
plugin_json_fake_marker_matches:
trusted_root / agent_definition_hash / respawn_result:
symlink_alias / real_path / deny_or_ask_result:
wrapper_case / decision / side_effect_absent:
sandbox_available / unsandboxed_fallback / network_policy:
decision: hold | limited-rollout | promote | rollback

Common mistakes

• Testing a redaction fix with a production token or password.
• Upgrading the terminal CLI while Desktop, IDE, CI, or an existing background process still runs an older binary.
• Assuming the patch retroactively removes secrets from old logs, tickets, or recordings.
• Rotating every credential with no exposure evidence, or refusing to rotate a credential that was clearly shared.
• Treating an untrusted-folder prompt test as proof of symlink rule enforcement, or the reverse.
• Calling permission analysis a sandbox. The release explicitly corrects messaging that overstated confinement.
• Recording only “a prompt appeared” instead of the final decision and side-effect state.

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FAQ

Does every installation older than 2.1.268 need all credentials rotated?

No. Upgrade the relevant launchers, then use actual diagnostic and retention evidence. Rotate a credential when it may have been rendered or shared, or when your incident policy requires rotation because exposure cannot be excluded. The release does not prove that every older installation leaked every configured secret.

Is putting an MCP secret in ${VAR} sufficient protection?

No. It keeps the literal value out of that settings field, but the process still resolves and uses it. Version 2.1.268 fixes named output paths that displayed resolved values; endpoint trust, tool permissions, environment inheritance, and log retention remain separate controls.

Does this release make project agent files safe by default?

It fixes a respawned teammate selecting a same-named agent file from an untrusted folder. You still need to decide which workspace is trusted, review project instructions, verify the effective tool inventory, and limit the operating-system identity running the agent.

Why test both a symlink and its real path?

Permission rules should protect the same object regardless of which equivalent path spelling reaches the checker. The 2.1.268 notes specifically name symlinked system directories, so both spellings belong in the acceptance evidence on hosts where the alias exists.

Sources

• Claude Code v2.1.268 release
• Claude Code v2.1.268 tagged changelog
• Claude Code security
• Claude Code plugin marketplaces
• Claude Code settings and permission rules

Originally published on IndieSeek.