CVE-2026-42506: golang.org/x/net/html · Cross-site Scripting
Affects golang.org/x/net/htmlSource CVE Database V5
Not known to be exploited · CVSS 6.1 Medium : upgrade to 0.55.0 when convenient.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 14% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 0.55.0
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 22 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade golang.org/x/net/html to 0.55.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| golang.org/x/netgolang.org/x/net/html | Affected
| Fixed in
|
Gogolang.org/x/net/htmlpkg:golang/golang.org/x/net/htmlOther threats | Affected
| Fixed in– |
Gogolang.org/x/net/htmlpkg:golang/golang.org/x/net/htmlOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
CVE-2026-42506 is a medium severity cross-site scripting (XSS) vulnerability in the golang.org/x/net/html package. It occurs when parsing arbitrary HTML and rendering it using the Render function produces an unexpected HTML tree. This improper neutralization of input during web page generation can allow XSS attacks in applications relying on this package for HTML sanitization. There are no known exploits in the wild at this time.