Cross-site scripting in github.com/yuin/goldmark/renderer/html
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Active
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- Partial Red Hat: 1 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-79.
Summary
Versions of the package github.com/yuin/goldmark/renderer/html before 1.7.17 are vulnerable to Cross-site Scripting (XSS) due to improper ordering of URL validation and normalization. The renderer validates link destinations using a prefix-based check (IsDangerousURL) before resolving HTML entities. This allows an attacker to bypass protocol filtering by encoding dangerous schemes using HTML5 named character references. For example, a payload such as javascript:alert(1) is not recognized as dangerous during validation, leading to arbitrary script execution in the context of applications that render the URL.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | github.com/yuin/goldmark/renderer/html | before 1.7.17 | 1.7.17 | Patch available | CNA |
| — | github.com/yuin/goldmark/renderer/html (Go) | before 1.7.17 | 1.7.17 | Patch available | GHSA-c97m-vxhj-p7j6 |
- github.com/yuin/goldmark/renderer/html Vendor— Affected before 1.7.17 Fixed in 1.7.17 Patch available CNA
- github.com/yuin/goldmark/renderer/html (Go) Vendor— Affected before 1.7.17 Fixed in 1.7.17 Patch available GHSA-c97m-vxhj-p7j6
Remediation
- Fix · CNA github.com/yuin/goldmark/renderer/html Fixed in 1.7.17
- Fix · GHSA-c97m-vxhj-p7j6 github.com/yuin/goldmark/renderer/html (Go) Fixed in 1.7.17 Advisory →
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Custom Metric Autoscaler operator for Red Hat Openshift | Affected | No fix yet: Fix deferred |
Timeline
- 2026-10-02 Threatist record created from CVE-2026-5160
- 2026-10-03 Alias added: GHSA-c97m-vxhj-p7j6
References
Sources
- CVE-2026-5160 · CVE Program
- CVE-2026-5160 · NVD
- FIRST EPSS
- GHSA-c97m-vxhj-p7j6 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-5160 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences