fix(security): add SSRF protection to browser_navigate#3058
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browser_navigate() only checked the website blocklist policy but did not call is_safe_url() to block private/internal addresses. This allowed the agent to navigate to localhost, cloud metadata endpoints (169.254.169.254), and private network IPs via the browser. web_tools and vision_tools already had this check. Added the same is_safe_url() pre-flight validation before the blocklist check in browser_navigate().
Move is_safe_url import to module level so it can be monkeypatched in tests. Update test_browser_navigate_returns_policy_block to mock _is_safe_url so the SSRF check passes and the policy check is reached.
Follow-up to cherry-picked PR #3041: 1. Fail-closed fallback: if url_safety module can't import, block all URLs instead of allowing all. Security guards should never fail-open. 2. Post-redirect SSRF check: after navigation, verify the final URL isn't a private/internal address. If a public URL redirected to 169.254.169.254 or localhost, navigate to about:blank and return an error — prevents the model from reading internal content via subsequent browser_snapshot calls.
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InB4DevOps
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Mar 25, 2026
…3058) * fix(security): add SSRF protection to browser_navigate browser_navigate() only checked the website blocklist policy but did not call is_safe_url() to block private/internal addresses. This allowed the agent to navigate to localhost, cloud metadata endpoints (169.254.169.254), and private network IPs via the browser. web_tools and vision_tools already had this check. Added the same is_safe_url() pre-flight validation before the blocklist check in browser_navigate(). * fix: move SSRF import to module level, fix policy test mock Move is_safe_url import to module level so it can be monkeypatched in tests. Update test_browser_navigate_returns_policy_block to mock _is_safe_url so the SSRF check passes and the policy check is reached. * fix(security): harden browser SSRF protection Follow-up to cherry-picked PR NousResearch#3041: 1. Fail-closed fallback: if url_safety module can't import, block all URLs instead of allowing all. Security guards should never fail-open. 2. Post-redirect SSRF check: after navigation, verify the final URL isn't a private/internal address. If a public URL redirected to 169.254.169.254 or localhost, navigate to about:blank and return an error — prevents the model from reading internal content via subsequent browser_snapshot calls. --------- Co-authored-by: 0xbyt4 <35742124+0xbyt4@users.noreply.github.com>
This was referenced Mar 26, 2026
outsourc-e
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Mar 26, 2026
…3058) * fix(security): add SSRF protection to browser_navigate browser_navigate() only checked the website blocklist policy but did not call is_safe_url() to block private/internal addresses. This allowed the agent to navigate to localhost, cloud metadata endpoints (169.254.169.254), and private network IPs via the browser. web_tools and vision_tools already had this check. Added the same is_safe_url() pre-flight validation before the blocklist check in browser_navigate(). * fix: move SSRF import to module level, fix policy test mock Move is_safe_url import to module level so it can be monkeypatched in tests. Update test_browser_navigate_returns_policy_block to mock _is_safe_url so the SSRF check passes and the policy check is reached. * fix(security): harden browser SSRF protection Follow-up to cherry-picked PR NousResearch#3041: 1. Fail-closed fallback: if url_safety module can't import, block all URLs instead of allowing all. Security guards should never fail-open. 2. Post-redirect SSRF check: after navigation, verify the final URL isn't a private/internal address. If a public URL redirected to 169.254.169.254 or localhost, navigate to about:blank and return an error — prevents the model from reading internal content via subsequent browser_snapshot calls. --------- Co-authored-by: 0xbyt4 <35742124+0xbyt4@users.noreply.github.com>
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there should be a flag to at least let user control the behaviour. this completly broke the local testing/fixing iteration loop. |
angelburgosrosado
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Apr 27, 2026
…3058) * fix(security): add SSRF protection to browser_navigate browser_navigate() only checked the website blocklist policy but did not call is_safe_url() to block private/internal addresses. This allowed the agent to navigate to localhost, cloud metadata endpoints (169.254.169.254), and private network IPs via the browser. web_tools and vision_tools already had this check. Added the same is_safe_url() pre-flight validation before the blocklist check in browser_navigate(). * fix: move SSRF import to module level, fix policy test mock Move is_safe_url import to module level so it can be monkeypatched in tests. Update test_browser_navigate_returns_policy_block to mock _is_safe_url so the SSRF check passes and the policy check is reached. * fix(security): harden browser SSRF protection Follow-up to cherry-picked PR NousResearch#3041: 1. Fail-closed fallback: if url_safety module can't import, block all URLs instead of allowing all. Security guards should never fail-open. 2. Post-redirect SSRF check: after navigation, verify the final URL isn't a private/internal address. If a public URL redirected to 169.254.169.254 or localhost, navigate to about:blank and return an error — prevents the model from reading internal content via subsequent browser_snapshot calls. --------- Co-authored-by: 0xbyt4 <35742124+0xbyt4@users.noreply.github.com>
This was referenced Apr 29, 2026
02356abc
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May 14, 2026
…3058) * fix(security): add SSRF protection to browser_navigate browser_navigate() only checked the website blocklist policy but did not call is_safe_url() to block private/internal addresses. This allowed the agent to navigate to localhost, cloud metadata endpoints (169.254.169.254), and private network IPs via the browser. web_tools and vision_tools already had this check. Added the same is_safe_url() pre-flight validation before the blocklist check in browser_navigate(). * fix: move SSRF import to module level, fix policy test mock Move is_safe_url import to module level so it can be monkeypatched in tests. Update test_browser_navigate_returns_policy_block to mock _is_safe_url so the SSRF check passes and the policy check is reached. * fix(security): harden browser SSRF protection Follow-up to cherry-picked PR NousResearch#3041: 1. Fail-closed fallback: if url_safety module can't import, block all URLs instead of allowing all. Security guards should never fail-open. 2. Post-redirect SSRF check: after navigation, verify the final URL isn't a private/internal address. If a public URL redirected to 169.254.169.254 or localhost, navigate to about:blank and return an error — prevents the model from reading internal content via subsequent browser_snapshot calls. --------- Co-authored-by: 0xbyt4 <35742124+0xbyt4@users.noreply.github.com>
olympus-terminal
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May 16, 2026
…3058) * fix(security): add SSRF protection to browser_navigate browser_navigate() only checked the website blocklist policy but did not call is_safe_url() to block private/internal addresses. This allowed the agent to navigate to localhost, cloud metadata endpoints (169.254.169.254), and private network IPs via the browser. web_tools and vision_tools already had this check. Added the same is_safe_url() pre-flight validation before the blocklist check in browser_navigate(). * fix: move SSRF import to module level, fix policy test mock Move is_safe_url import to module level so it can be monkeypatched in tests. Update test_browser_navigate_returns_policy_block to mock _is_safe_url so the SSRF check passes and the policy check is reached. * fix(security): harden browser SSRF protection Follow-up to cherry-picked PR NousResearch#3041: 1. Fail-closed fallback: if url_safety module can't import, block all URLs instead of allowing all. Security guards should never fail-open. 2. Post-redirect SSRF check: after navigation, verify the final URL isn't a private/internal address. If a public URL redirected to 169.254.169.254 or localhost, navigate to about:blank and return an error — prevents the model from reading internal content via subsequent browser_snapshot calls. --------- Co-authored-by: 0xbyt4 <35742124+0xbyt4@users.noreply.github.com>
gweeteve
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Jun 2, 2026
…3058) * fix(security): add SSRF protection to browser_navigate browser_navigate() only checked the website blocklist policy but did not call is_safe_url() to block private/internal addresses. This allowed the agent to navigate to localhost, cloud metadata endpoints (169.254.169.254), and private network IPs via the browser. web_tools and vision_tools already had this check. Added the same is_safe_url() pre-flight validation before the blocklist check in browser_navigate(). * fix: move SSRF import to module level, fix policy test mock Move is_safe_url import to module level so it can be monkeypatched in tests. Update test_browser_navigate_returns_policy_block to mock _is_safe_url so the SSRF check passes and the policy check is reached. * fix(security): harden browser SSRF protection Follow-up to cherry-picked PR NousResearch#3041: 1. Fail-closed fallback: if url_safety module can't import, block all URLs instead of allowing all. Security guards should never fail-open. 2. Post-redirect SSRF check: after navigation, verify the final URL isn't a private/internal address. If a public URL redirected to 169.254.169.254 or localhost, navigate to about:blank and return an error — prevents the model from reading internal content via subsequent browser_snapshot calls. --------- Co-authored-by: 0xbyt4 <35742124+0xbyt4@users.noreply.github.com>
Egavasyug
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Jun 10, 2026
…3058) * fix(security): add SSRF protection to browser_navigate browser_navigate() only checked the website blocklist policy but did not call is_safe_url() to block private/internal addresses. This allowed the agent to navigate to localhost, cloud metadata endpoints (169.254.169.254), and private network IPs via the browser. web_tools and vision_tools already had this check. Added the same is_safe_url() pre-flight validation before the blocklist check in browser_navigate(). * fix: move SSRF import to module level, fix policy test mock Move is_safe_url import to module level so it can be monkeypatched in tests. Update test_browser_navigate_returns_policy_block to mock _is_safe_url so the SSRF check passes and the policy check is reached. * fix(security): harden browser SSRF protection Follow-up to cherry-picked PR NousResearch#3041: 1. Fail-closed fallback: if url_safety module can't import, block all URLs instead of allowing all. Security guards should never fail-open. 2. Post-redirect SSRF check: after navigation, verify the final URL isn't a private/internal address. If a public URL redirected to 169.254.169.254 or localhost, navigate to about:blank and return an error — prevents the model from reading internal content via subsequent browser_snapshot calls. --------- Co-authored-by: 0xbyt4 <35742124+0xbyt4@users.noreply.github.com>
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Summary
Salvage of PR #3041 by @0xbyt4 — cherry-picked onto current main with two hardening improvements.
browser_navigate()hadcheck_website_access()(domain blocklist) but was missingis_safe_url()(SSRF/private IP check). The agent could navigate the browser to127.0.0.1,169.254.169.254(cloud metadata),192.168.x.x, etc. The other URL-capable tools (web_tools.py,vision_tools.py) already had this check.Follow-up hardening
Fail-closed fallback: Changed the import fallback from
lambda url: True(allow all) tolambda url: False(block all). Security guards should never fail-open — if theurl_safetymodule can't import, block everything rather than allowing SSRF.Post-redirect SSRF check: After navigation, verifies the final URL isn't a private/internal address. If a public URL redirected to
169.254.169.254or localhost, navigates toabout:blankand returns an error. This prevents the model from reading internal content via subsequentbrowser_snapshotcalls. Mirrors the redirect protection already invision_tools.py.Tests
6175 passed. 4 pre-existing cron failures (unrelated).
Closes #3041