CVE-2026-39399
Last modified
CVE-2026-39399 is a critical-severity vulnerability rated 9.6/10 on the CVSS scale. NuGet Gallery is a package repository that powers nuget.org. A security vulnerability exists in the NuGetGallery backend job’s handling of .nuspec files within NuGet packages. EPSS estimates a 0.53% chance of exploitation in the next 30 days.
Description
NuGet Gallery is a package repository that powers nuget.org. A security vulnerability exists in the NuGetGallery backend job’s handling of .nuspec files within NuGet packages. An attacker can supply a crafted nuspec file with malicious metadata, leading to cross package metadata injection that may result in remote code execution (RCE) and/or arbitrary blob writes due to insufficient input validation. The issue is exploitable via URI fragment injection using unsanitized package identifiers, allowing an attacker to control the resolved blob path. This enables writes to arbitrary blobs within the storage container, not limited to .nupkg files, resulting in potential tampering of existing content. This issue has been patched in commit 0e80f87628349207cdcaf55358491f8a6f1ca276.
Metrics
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| NuGet | NuGetGallery | < 0e80f87628349207cdcaf55358491f8a6f1ca276 |
References
Timeline
- Published
- Last Modified
- Status
- Awaiting Analysis
Frequently Asked Questions
What is CVE-2026-39399?
How severe is CVE-2026-39399?
How do I fix CVE-2026-39399?
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2026
- CVE-2026-39393CI4MS is a CodeIgniter 4-based CMS skeleton that delivers a …8.1
- CVE-2026-39394CI4MS is a CodeIgniter 4-based CMS skeleton that delivers a …9.8
- CVE-2026-39395Cosign provides code signing and transparency for containers…5.3
- CVE-2026-39396OpenBao is an open source identity-based secrets management …6.5
- CVE-2026-39397@delmaredigital/payload-puck is a PayloadCMS plugin for inte…9.8
- CVE-2026-39398Rejected reason: The affected product and advisory are not p…
- CVE-2026-3940Insufficient policy enforcement in DevTools in Google Chrome…5.3
- CVE-2026-39400Cronicle is a multi-server task scheduler and runner, with a…6.1
- CVE-2026-39401Cronicle is a multi-server task scheduler and runner, with a…5.4
- CVE-2026-39402lxc is a Linux container runtime. In the setuid helper lxc-u…6.5
- CVE-2026-39405Frappe Learning Management System (LMS) is a learning system…9.4
- CVE-2026-39406@hono/node-server allows running the Hono application on Nod…5.3
Are you affected by CVE-2026-39399?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST
