Vulnerability library
Security checkJuly 02, 2026

@asymmetric-effort/specifyjs: CSS expression sanitization is bypassable in renderToString

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Description

Location: core/src/server/render-to-string.ts:307-311

CSS value sanitization stripped expression( and url(javascript: using simple regex, but could be bypassed with CSS unicode escapes (\65xpression(), null bytes, or CSS comments (exp/**/ression().

Recommendation

Update the @asymmetric-effort/specifyjs package to the latest compatible version. Followings are version details:

  • Affected version(s): < 0.2.136
  • Patched version(s): 0.2.136

References

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Related Issues

See something that needs correcting? Let us knowUpdated July 02, 2026