CVE-2026-16729
4.8 · MEDIUMOverview
CVE-2026-16729 is a medium-severity vulnerability affecting nodejs undici. It was published on July 29, 2026 and has a CVSS 3.1 base score of 4.8 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 4.8, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
undici's setCookie function does not fully sanitize cookie attributes. In undici before 6.28.0, from 7.0.0 up to before 7.29.0, and from 8.0.0 up to before 8.9.0, a domain value is not checked for semicolons and entries in the unparsed array are not sanitized, so attacker-influenced input can inject additional cookie attributes. For example, a domain value containing a semicolon can append attributes such as SameSite, and an unparsed entry can inject attributes such as HttpOnly, without the caller setting them. Applications that pass user-controlled input to these fields, such as multi-tenant or reverse-proxy servers that scope session cookies to a tenant-supplied domain, can have SameSite CSRF protections bypassed, or the Secure, HttpOnly, and SameSite attributes forced, stripped, or overridden. The issue is fixed in undici 6.28.0, 7.29.0, and 8.9.0.
Remediation
Check the references section for vendor advisories and patches from nodejs. Update undici to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| nodejs | undici | >= 0, < 6.28.0 | Affected |
Frequently Asked Questions
What is CVE-2026-16729?
CVE-2026-16729 is a medium-severity vulnerability affecting nodejs undici. It was published on July 29, 2026 and has a CVSS 3.1 base score of 4.8 (MEDIUM).
How severe is CVE-2026-16729?
This vulnerability has a CVSS 3.1 base score of 4.8, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-16729?
Check the references section for vendor advisories and patches from nodejs. Update undici to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-16729?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-16729 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
Automated penetration testing that runs continuously, not just quarterly.
AI-driven PR review catches vulnerable dependencies before they ship.
Browser-based exploitation validates findings with real proof-of-concept.
Related MEDIUM CVEs from 2026
View all →Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, a
In libexpat before 2.7.4, the doContent function does not properly determine the buffer size bufSize
Buffer overflow vulnerability in the HDC module. Impact: Successful exploitation of this vulnerabili
ImageMagick is free and open-source software used for editing and manipulating digital images. Prior
A improper certificate validation vulnerability in Fortinet FortiAnalyzer 7.6.0 through 7.6.4, Forti
OpenClaw versions prior to 2026.3.1 fail to properly handle authentication bootstrap errors during s
File Browser is a file managing interface for uploading, deleting, previewing, renaming, and editing
Vulnerability of improper permission control in the theme setting module. Impact: Successful exploit
Access of resource using incompatible type ('type confusion') vulnerability in Samsung Open Source E
A flaw was found in Keycloak, specifically in the organization selection login page. A remote attack
Serendipity is a PHP-powered weblog engine. In versions 2.6-beta2 and below, the serendipity_setCoo
In iTerm2 through 3.6.9, displaying a .txt file can cause code execution via DCS 2000p and OSC 135 d