CVE-2026-39399 (GCVE-0-2026-39399)

Vulnerability from cvelistv5 – Published: 2026-04-14 23:01 – Updated: 2026-04-15 14:42
VLAI
Title
NuGet Gallery: Arbitrary Blob Overwrite via Nuspec Confusion and URI Fragment Truncation
Summary
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.
Severity
9.6 (Critical)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-15 14:41 UTC
CWE
  • CWE-20 - Improper Input Validation
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7851 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
NuGet NuGetGallery Affected: < 0e80f87628349207cdcaf55358491f8a6f1ca276
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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