CVE-2025-0913

Description

os.OpenFile(path, os.O_CREATE|O_EXCL) behaved differently on Unix and Windows systems when the target path was a dangling symlink. On Unix systems, OpenFile with O_CREATE and O_EXCL flags never follows symlinks. On Windows, when the target path was a symlink to a nonexistent location, OpenFile would create a file in that location. OpenFile now always returns an error when the O_CREATE and O_EXCL flags are both set and the target path is a symlink.

CVSS Metrics

• v3.1•MEDIUM•Score: 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

EPSS Trends

Current EPSS score: 0.04%• Percentile: 12%

Techniques & Countermeasures

• CWE-59•Improper Link Resolution Before File Access ('Link Following')

  The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

Affected Systems

• go standard library•os

  < 1.23.10 | ≥ 1.24.0-0, < 1.24.4

• go standard library•syscall

  < 1.23.10 | ≥ 1.24.0-0, < 1.24.4

• golang•go

  < 1.23.10 | ≥ 1.24.0, < 1.24.4

• Go•stdlib

  ≥ 1.24.0-0, < 1.24.4

References (4)

• https://go.dev/cl/672396
• https://go.dev/issue/73702
• https://groups.google.com/g/golang-announce/c/ufZ8WpEsA3A
• https://pkg.go.dev/vuln/GO-2025-3750