CVE-2021-21237 Git LFS can execute a Git binary from the current directory on Windows

2021-01-1517:36:09

CWE-426

GitHub_M

www.cve.org

cve-2021-21237

git lfs

windows

git binary

arbitrary code

incomplete fix

security vulnerability

CVSS3

7.2

Attack Vector

LOCAL

Attack Complexity

HIGH

Privileges Required

LOW

User Interaction

REQUIRED

Scope

CHANGED

Confidentiality Impact

HIGH

Integrity Impact

HIGH

Availability Impact

NONE

CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N

AI Score

9.1

Confidence

High

EPSS

0.952

Percentile

99.4%

JSON

Git LFS is a command line extension for managing large files with Git. On Windows, if Git LFS operates on a malicious repository with a git.bat or git.exe file in the current directory, that program would be executed, permitting the attacker to execute arbitrary code. This does not affect Unix systems. This is the result of an incomplete fix for CVE-2020-27955. This issue occurs because on Windows, Go includes (and prefers) the current directory when the name of a command run does not contain a directory separator. Other than avoiding untrusted repositories or using a different operating system, there is no workaround. This is fixed in v2.13.2.

CNA Affected

[
  {
    "product": "git-lfs",
    "vendor": "git-lfs",
    "versions": [
      {
        "status": "affected",
        "version": "< 2.13.2"
      }
    ]
  }
]