CVE-2026-39822

On Unix systems, opening a file in an os.Root improperly follows symlinks to locations outside of the Root when the final path component of the a path is a symbolic link and the path ends in /. For example, 'root.Open("symlink/")' will open "symlink" even when "symlink" is a symbolic link pointing outside of the root.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://go.dev/cl/797880	Patch
https://go.dev/issue/79005	Issue Tracking Patch
https://groups.google.com/g/golang-announce/c/OrmQE_Yp5Sc	Mailing List Patch Vendor Advisory
https://pkg.go.dev/vuln/GO-2026-4970	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:golang:go::::::::
	cpe:2.3:a:golang:go::::::::
	cpe:2.3:a:golang:go:1.27:rc1::::::

History

25 Oct 2026, 17:10

Type	Values Removed	Values Added
Summary		(es) En sistemas Unix, abrir un archivo en un os.Root sigue incorrectamente los enlaces simbólicos a ubicaciones fuera del Root cuando el componente final de una ruta es un enlace simbólico y la ruta termina en /. Por ejemplo, ’root.Open(“symlink/”)’ abrirá “symlink” incluso cuando “symlink” es un enlace simbólico que apunta fuera de la raíz.

Information

Published : 2026-07-08 17:17

Updated : 2026-10-25 17:10

NVD link : CVE-2026-39822

Mitre link : CVE-2026-39822

CVE.ORG link : CVE-2026-39822

JSON object : View

Products Affected

golang

go

CWE

CWE-61

UNIX Symbolic Link (Symlink) Following

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