Vulnerability · Published Mar 6, 2026 · Assigned by Go
CVE-2026-27142URLs in meta content attribute actions are not escaped in html/template
Medium 6.1
In plain English
A medium-severity security flaw in html/template from Go standard library. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 32% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Actions which insert URLs into the content attribute of HTML meta tags are not escaped. This can allow XSS if the meta tag also has an http-equiv attribute with the value "refresh". A new GODEBUG setting has been added, htmlmetacontenturlescape, which can be used to disable escaping URLs in actions in the meta content attribute which follow "url=" by setting htmlmetacontenturlescape=0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.23 | go | 1.25.8-r0 | ALPINE-CVE-2026-27142 |
| Alpine:v3.24 | go | 1.25.8-r0 | ALPINE-CVE-2026-27142 |
| Alpine:v3.24 | rclone | 1.73.5-r0 | ALPINE-CVE-2026-27142 |
| Debian:12 | golang-1.19 | no fix listed | DEBIAN-CVE-2026-27142 |
| Debian:13 | golang-1.24 | no fix listed | DEBIAN-CVE-2026-27142 |
| Debian:14 | golang-1.26 | 1.26.1-1 | DEBIAN-CVE-2026-27142 |
| Go | stdlib | 1.25.8, 1.26.1 | GO-2026-4603 |
| Ubuntu:22.04:LTS | golang-1.24 | no fix listed | UBUNTU-CVE-2026-27142 |
| Ubuntu:24.04:LTS | golang-1.24 | no fix listed | UBUNTU-CVE-2026-27142 |
| Ubuntu:25.10 | golang-1.24 | no fix listed | UBUNTU-CVE-2026-27142 |
| Ubuntu:26.04:LTS | golang-1.24 | no fix listed | UBUNTU-CVE-2026-27142 |
| Ubuntu:22.04:LTS | golang-1.25 | no fix listed | UBUNTU-CVE-2026-27142 |
| Ubuntu:24.04:LTS | golang-1.25 | no fix listed | UBUNTU-CVE-2026-27142 |
| Ubuntu:25.10 | golang-1.25 | no fix listed | UBUNTU-CVE-2026-27142 |
| Ubuntu:26.04:LTS | golang-1.25 | no fix listed | UBUNTU-CVE-2026-27142 |
| Ubuntu:22.04:LTS | golang-1.26 | no fix listed | UBUNTU-CVE-2026-27142 |
| Ubuntu:24.04:LTS | golang-1.26 | no fix listed | UBUNTU-CVE-2026-27142 |
| Ubuntu:26.04:LTS | golang-1.26 | no fix listed | UBUNTU-CVE-2026-27142 |
| Ubuntu:26.10 | golang-1.26 | no fix listed | UBUNTU-CVE-2026-27142 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Go standard library | html/template | 0 – before 1.25.81.26.0-0 – before 1.26.1 |