fix(vision): reject non-image files and blocked URLs - #1940
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#1940) Three safety gaps in vision_analyze_tool: 1. Local files accepted without checking if they're actually images — a renamed text file would get base64-encoded and sent to the model. Now validates magic bytes (PNG, JPEG, GIF, BMP, WebP, SVG). 2. No website policy enforcement on image URLs — blocked domains could be fetched via the vision tool. Now checks before download. 3. No redirect check — if an allowed URL redirected to a blocked domain, the download would proceed. Now re-checks the final URL. Fixed one test that needed _validate_image_url mocked to bypass DNS resolution on the fake blocked.test domain (is_safe_url does DNS checks that were added after the original PR). Co-authored-by: GutSlabs <GutSlabs@users.noreply.github.com>
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#1940) (#3845) Three safety gaps in vision_analyze_tool: 1. Local files accepted without checking if they're actually images — a renamed text file would get base64-encoded and sent to the model. Now validates magic bytes (PNG, JPEG, GIF, BMP, WebP, SVG). 2. No website policy enforcement on image URLs — blocked domains could be fetched via the vision tool. Now checks before download. 3. No redirect check — if an allowed URL redirected to a blocked domain, the download would proceed. Now re-checks the final URL. Fixed one test that needed _validate_image_url mocked to bypass DNS resolution on the fake blocked.test domain (is_safe_url does DNS checks that were added after the original PR). Co-authored-by: GutSlabs <GutSlabs@users.noreply.github.com>
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Merged via #3845. Cherry-picked cleanly onto current main with one test fix (mocked _validate_image_url to bypass newer DNS resolution checks on fake test domains). All three security fixes verified end-to-end: non-image rejection, website policy enforcement, and redirect re-check. Thanks for the solid contribution! |
angelburgosrosado
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NousResearch#1940) (NousResearch#3845) Three safety gaps in vision_analyze_tool: 1. Local files accepted without checking if they're actually images — a renamed text file would get base64-encoded and sent to the model. Now validates magic bytes (PNG, JPEG, GIF, BMP, WebP, SVG). 2. No website policy enforcement on image URLs — blocked domains could be fetched via the vision tool. Now checks before download. 3. No redirect check — if an allowed URL redirected to a blocked domain, the download would proceed. Now re-checks the final URL. Fixed one test that needed _validate_image_url mocked to bypass DNS resolution on the fake blocked.test domain (is_safe_url does DNS checks that were added after the original PR). Co-authored-by: GutSlabs <GutSlabs@users.noreply.github.com>
02356abc
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NousResearch#1940) (NousResearch#3845) Three safety gaps in vision_analyze_tool: 1. Local files accepted without checking if they're actually images — a renamed text file would get base64-encoded and sent to the model. Now validates magic bytes (PNG, JPEG, GIF, BMP, WebP, SVG). 2. No website policy enforcement on image URLs — blocked domains could be fetched via the vision tool. Now checks before download. 3. No redirect check — if an allowed URL redirected to a blocked domain, the download would proceed. Now re-checks the final URL. Fixed one test that needed _validate_image_url mocked to bypass DNS resolution on the fake blocked.test domain (is_safe_url does DNS checks that were added after the original PR). Co-authored-by: GutSlabs <GutSlabs@users.noreply.github.com>
gweeteve
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NousResearch#1940) (NousResearch#3845) Three safety gaps in vision_analyze_tool: 1. Local files accepted without checking if they're actually images — a renamed text file would get base64-encoded and sent to the model. Now validates magic bytes (PNG, JPEG, GIF, BMP, WebP, SVG). 2. No website policy enforcement on image URLs — blocked domains could be fetched via the vision tool. Now checks before download. 3. No redirect check — if an allowed URL redirected to a blocked domain, the download would proceed. Now re-checks the final URL. Fixed one test that needed _validate_image_url mocked to bypass DNS resolution on the fake blocked.test domain (is_safe_url does DNS checks that were added after the original PR). Co-authored-by: GutSlabs <GutSlabs@users.noreply.github.com>
waefrebeorn
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NousResearch#1940) (NousResearch#3845) Three safety gaps in vision_analyze_tool: 1. Local files accepted without checking if they're actually images — a renamed text file would get base64-encoded and sent to the model. Now validates magic bytes (PNG, JPEG, GIF, BMP, WebP, SVG). 2. No website policy enforcement on image URLs — blocked domains could be fetched via the vision tool. Now checks before download. 3. No redirect check — if an allowed URL redirected to a blocked domain, the download would proceed. Now re-checks the final URL. Fixed one test that needed _validate_image_url mocked to bypass DNS resolution on the fake blocked.test domain (is_safe_url does DNS checks that were added after the original PR). Co-authored-by: GutSlabs <GutSlabs@users.noreply.github.com>
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What does this PR do?
Fixes two safety issues in
vision_analyze_tool().Previously:
That meant non-image local files could be base64-encoded and sent to the vision model, and blocked remote URLs could bypass the website policy layer.
This change validates that local files are real images, enforces website policy checks before and after download redirects, and adds regression tests.
Type of Change
Changes Made
How to Test
source .venv/bin/activatepytest tests/tools/test_vision_tools.py -q