GHSA-x4hg-hfwf-p9mwPublished

@asymmetric-effort/nogginlessdom vulnerable to ReDoS via user-controlled regex in HTMLInputElement pattern validation

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osv · GHSA-x4hg-hfwf-p9mw

Published

## Summary The `HTMLInputElement.checkValidity()` method constructed a `RegExp` directly from the user-controlled `pattern` property without any sanitization or timeout protection. This allowed an attacker to inject a regex with catastrophic backtracking, freezing the event loop. ## Fix Fixed in commit https://github.com/asymmetric-effort/NogginLessDom/commit/25a3cbac665fae5663f8b71c073b80c3152dbe7b on `main`. Added: - Pattern length limit (1024 characters) - Nested quantifier detection (`hasNestedQuantifiers`) that rejects patterns like `(a+)+` before constructing the regex - Patterns exceeding limits are treated as non-matching (safe default)

Source published: 2 Jul 2026 20:20:04 UTC
Source modified: 10 Sep 2026 03:50:53 UTC
Saved here: 24 Oct 2026 13:17:17 UTC
Source terms: GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

Source: osv · GitHub Advisory Database · CC-BY-4.0. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

Publisher rating · MODERATE