Cloud metadata endpoints (169.254.169.254 etc.) are now always blocked
by browser_navigate regardless of hybrid routing, allow_private_urls,
or backend.
Bug: commit 42c076d3 (#16136) added hybrid routing that flips
auto_local_this_nav=True for private URLs and short-circuits
_is_safe_url(). IMDS endpoints are technically private (169.254/16
link-local), so the sidecar happily routed them to a local Chromium,
and the agent could read IAM credentials via browser_snapshot. On
EC2/GCP/Azure this is a full SSRF-to-credential-theft.
Fix: new is_always_blocked_url() in url_safety.py — a narrow floor
that checks _BLOCKED_HOSTNAMES, _ALWAYS_BLOCKED_IPS,
_ALWAYS_BLOCKED_NETWORKS only. Applied as an independent gate in
browser_navigate's pre-nav and post-redirect checks, BEFORE
auto_local_this_nav gets a chance to short-circuit. Ordinary private
URLs (localhost, 192.168.x, 10.x, .local, CGNAT) still route to the
local sidecar as the #16136 feature intends.
Secondary fix (reporter's finding): _url_is_private() now explicitly
checks 172.16.0.0/12. ipaddress.is_private only covers that range on
Python ≥3.11 (bpo-40791), so on 3.10 runtimes those URLs were routed
to cloud instead of the local sidecar. No security impact — just a
correctness fix for the hybrid-routing feature.
Closes#16234.
The SSRF protection added in #3041 blocks all private/internal addresses
unconditionally in browser_navigate(). This prevents legitimate local use
cases (localhost apps, LAN devices) when using Camofox or the built-in
headless Chromium without a cloud provider.
The check is only meaningful for cloud backends (Browserbase, BrowserUse)
where the agent could reach internal resources on a remote machine. Local
backends give the user full terminal and network access already — the
SSRF check adds zero security value.
Add _is_local_backend() helper that returns True when Camofox is active
or no cloud provider is configured. Both the pre-navigation and
post-redirect SSRF checks now skip when running locally. The
browser.allow_private_urls config option remains available as an
explicit opt-out for cloud mode.
* fix(tools): skip SSRF check in local browser mode
The SSRF protection added in #3041 blocks all private/internal
addresses unconditionally in browser_navigate(). This prevents
legitimate local development use cases (localhost testing, LAN
device access) when using the local Chromium backend.
The SSRF check is only meaningful for cloud browsers (Browserbase,
BrowserUse) where the agent could reach internal resources on a
remote machine. In local mode, the user already has full terminal
and network access, so the check adds no security value.
This change makes the SSRF check conditional on _get_cloud_provider(),
keeping full protection in cloud mode while allowing private addresses
in local mode.
* fix(tools): make SSRF check configurable via browser.allow_private_urls
Replace unconditional SSRF check with a configurable setting.
Default (False) keeps existing security behavior. Setting to True
allows navigating to private/internal IPs for local dev and LAN use cases.
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Co-authored-by: Nils (Norya) <nils@begou.dev>
