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🛡️ Sentinel: Fix XXE vulnerability in SVG parser #21

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Merged
alexey1312 merged 4 commits into from
Dec 29, 2025
Merged

🛡️ Sentinel: Fix XXE vulnerability in SVG parser #21

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1267012
feat(security): disable external entity loading in SVG parser
google-labs-jules[bot] Dec 28, 2025
9bf3069
feat(security): disable external entity loading in SVG parser
google-labs-jules[bot] Dec 28, 2025
b472fe2
feat(security): disable external entity loading in SVG parser
google-labs-jules[bot] Dec 29, 2025
eb478e5
feat(security): disable external entity loading in SVG parser
google-labs-jules[bot] Dec 29, 2025
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5 changes: 5 additions & 0 deletions .jules/sentinel.md
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Original file line number Diff line number Diff line change
@@ -0,0 +1,5 @@
## 2024-05-22 - [XXE Protection in SVG Parser]

**Vulnerability:** The `XMLDocument` initializer in `SVGParser.swift` used empty options `[]`, which potentially allows XML External Entity (XXE) attacks if the underlying parser defaults are permissive.
**Learning:** Even when using higher-level abstractions like `XMLDocument`, one must explicitly disable dangerous features like external entity loading when processing untrusted input.
**Prevention:** Always use `.nodeLoadExternalEntitiesNever` (or equivalent flags in other parsers) when parsing XML/SVG data from external sources.
4 changes: 3 additions & 1 deletion Sources/SVGKit/SVGParser.swift
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Expand Up @@ -327,7 +327,9 @@ public final class SVGParser: @unchecked Sendable { // swiftlint:disable:this ty
data
}

let document = try XMLDocument(data: svgData, options: [])
// Disable external entity loading to prevent XXE attacks
let options: XMLNode.Options = [.nodeLoadExternalEntitiesNever]
let document = try XMLDocument(data: svgData, options: options)
guard let root = document.rootElement(), elementName(root) == "svg" else {
throw SVGParserError.invalidSVGRoot
}
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