Medium severity · published Feb 5, 2026
CVE-2025-47911
Quadratic parsing complexity in golang.org/x/net/html
5.3
CVSS
0.6%
EPSS
No
On KEV
Description
The html.Parse function in golang.org/x/net/html has quadratic parsing complexity when processing certain inputs, which can lead to denial of service (DoS) if an attacker provides specially crafted HTML content.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 47% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
GO
golang.org/x/net/html · golang.org/x/net
before 0.45.0 · source: vendor
HT
Html · GO
before 0.45.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-47911
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-47911
Issue Tracking
https://github.com/golang/vulndb/issues/4440
Patch
https://go.dev/cl/709876
Mailing List
https://groups.google.com/g/golang-announce/c/jnQcOYpiR2c
Vendor Advisory
https://pkg.go.dev/vuln/GO-2026-4440
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