CVE-2026-78661: Avoid quadratic complexity when coalescing text nodes in html in golang.org/x/net
golang.org/x/net · golang.org/x/net/html
Vendor fix available · Affected: golang.org/x/net/html · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 35% of scored CVEs
DescriptionCVE.org
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.
Affected products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- golang.org/x/net · golang.org/x/net/htmlbefore 0.62.0
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Unlikely (under 1%). EPSS under 1%, or no score yet.
- CISA KEV
- Not listed
- Public check
- No public nuclei template
- Vendor
- golang.org/x/net
- Published
- October 2026
CoverageNo articles yet
No CyberSIXT article names CVE-2026-78661 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.