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Andre Vasconcelos
13a0d63b3c
* MM-67372: Filter SVG images from OpenGraph metadata to prevent DoS This commit adds server-side filtering of SVG images from OpenGraph metadata to mitigate a DoS vulnerability where malicious SVG images in og:image tags can crash Chromium-based browsers and Safari. Changes: - Add IsSVGImageURL() helper function in model package to detect SVG URLs - Filter SVG images in parseOpenGraphMetadata() for regular HTML pages - Filter SVG images in parseOpenGraphFromOEmbed() for oEmbed responses - Add defense-in-depth filtering in TruncateOpenGraph() and getImagesForPost() - Add comprehensive tests for all SVG filtering functionality SVG detection is based on: - File extension (.svg, .svgz) - case-insensitive - MIME type (image/svg+xml) Reference: https://issues.chromium.org/issues/40057345 * MM-67372: Filter SVG images from cache/DB and direct SVG URLs This commit addresses remaining attack vectors for the SVG DoS vulnerability: 1. Cache/DB filtering: Apply TruncateOpenGraph when returning OpenGraph from cache or database to filter stale data that was stored before the initial fix was deployed. 2. Direct SVG URLs: Filter PostImage entries with Format="svg" to prevent browser crashes when someone posts a direct link to an SVG file. 3. Embed creation: Skip creating image embeds for SVG images and create link embeds instead. 4. New SVG detection: Return nil instead of creating PostImage when fetching direct SVG URLs to prevent storing them in the database. These changes ensure that even environments with pre-existing malicious link metadata will be protected after a server restart. * MM-67372: Fix test expectation for SVG image handling * Removed duplicate logic in favor of already implemented FilterSVGImages in model * Addressing PR comments * Replacing exact match comparison with prefix check * Added new test cases for unit tests