Changelog

All notable changes to phil/svg-sanitizer will be documented in this file.

Updates should follow the Keep a CHANGELOG principles.

0.1.0-alpha - 2026-11-11

Added

• SvgSanitizer: sanitize() reads an image as XML without network, document type nor entities, and writes anew, in the SVG namespace and without XML declaration, the elements and attributes the policy keeps, their text, and nothing else; returns Sanitized — the SVG, empty when the image is refused whole — and each Removal with its RemovalReason, subject and line, the first Sanitized::MAX_REMOVALS (100) listed and the others counted in omittedRemovals. An image is read in UTF-8 only: one with a null byte, as UTF-16 and UTF-32 have, or with bytes that are not UTF-8 is refused as malformed.
• Policy: allow lists of elements and attributes for static drawings — structure, shapes, text, paint servers, clipping, masks, markers, filters, raster images —, SMIL animation by withAnimations(), the schemes of links, raster images in data: addresses, the CSS policy of the image, limits of size, depth, number of elements and attributes per element (maxAttributes, 256 by default, counted in one pass before the image is parsed, refused whole as TooManyAttributes); safe inline by default: <style> left out unless withStyleElements(true), new Policy(styleElements: true) or withElements('style') allows it, and every id, with every fragment of href, xlink:href and url() that points to one, written after withIdPrefix()'s prefix, svg- by default, null to keep them as written; the elements that run code or embed a document (script, foreignObject, iframe, object, embed…), event handlers, xml:base and links to javascript:, data: and their kind can never be allowed (InvalidPolicy).
• References checked: href and xlink:href to a fragment of the image; a PNG, JPEG, GIF, WebP or AVIF image in a data: address on <image> and <feImage>; a link of an allowed scheme on <a>, the whitespace and control characters of its scheme ignored as browsers ignore them.
• CSS through phil/css-sanitizer: style attributes as declarations, allowed <style> elements as style sheets held inside the image — every rule placed under an id written from the image's content (the prefix, drawing- and sixteen hexadecimal digits of its SHA-256), which replaces the root's id, every reference to it rewritten, so that two images on one page whose roots share an id never share a rule, a selector that already starts with that id kept as the image wrote it when it reaches nothing but the root and what lies inside it, the ids of selectors prefixed, @import, @page, @font-face and every URL but a fragment removed —, and the presentation attributes and transform lists that hold more than names, numbers and colours as the value of their property, every url() but a fragment refused.
• Animations that target a reference, a style or an event handler, and values of animation that hold a function or a scheme, removed.
• Processing instructions removed and reported; comments and document types left out.
• SvgSanitizerException, implemented by InvalidPolicy.
• Validator\SafeSvg, a symfony/validator constraint, and SafeSvgValidator: each removal of the sanitizer a violation, NOT_ALLOWED_ERROR, and an image refused whole one violation, REFUSED_ERROR, with the reason, subject and line as parameters; the removals past the first 100 one more violation, moreMessage, with their count; null and the empty string valid; the policy the one of the sanitizer the validator is built with.
• The documentation in doc/, one file per topic, indexed by the README.
• CONTRIBUTING.md, SECURITY.md and CODE_OF_CONDUCT.md.