Vulnerability Description
When coalescing adjacent text nodes in addText and fosterParent, appending to an existing TextNode's Data via string concatenation (n.Data += text) reallocated and copied the accumulated string on every token. Inputs containing many short text runs separated by ignored end tags (such as "a</x>") caused O(n^2) allocations and byte copies. Accumulate coalesced text in per-node byte slices during parsing and materialize Data strings once at the end of parse.
References
- https://go.dev/cl/849365
- https://go.dev/issue/82224
- https://groups.google.com/g/golang-announce/c/sqrs2vTx_Xs
- https://pkg.go.dev/vuln/GO-2026-6860
FAQ
What is CVE-2026-78661?
CVE-2026-78661 is a documented vulnerability. When coalescing adjacent text nodes in addText and fosterParent, appending to an existing TextNode's Data via string concatenation (n.Data += text) reallocated and copied the accumulated string on eve...
How severe is CVE-2026-78661?
CVSS scoring is not yet available for CVE-2026-78661. Check NVD for updates.
Is there a patch for CVE-2026-78661?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.