Vulnerability · Published Jan 15, 2021 · Assigned by GitHub_M

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

High 7.2

In plain English

A high-severity security flaw in git-lfs from git-lfs. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 40% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.2High

Exploit odds (30 days)0.5%top 60.5% of all CVEs

Exploited in the wildNo reportsnot in CISA KEV

Attack toolingNoneno public tooling known

Official description

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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Go	github.com/git-lfs/git-lfs	2.13.2	GHSA-cx3w-xqmc-84g5
Go	github.com/git-lfs/git-lfs	1.5.1-0.20210113180018-fc664697ed2c	GO-2021-0098

Affected products (as reported)

Vendor	Product	Versions
git-lfs	git-lfs	< 2.13.2

Weakness: CWE-426 · Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N

References

https://github.com/git-lfs/git-lfs/security/advisories/GHSA-cx3w-xqmc-84g5 x_refsource_CONFIRM
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-27955 x_refsource_MISC
https://github.com/git-lfs/git-lfs/releases/tag/v2.13.2 x_refsource_MISC
https://github.com/git-lfs/git-lfs/commit/fc664697ed2c2081ee9633010de0a7f9debea72a x_refsource_MISC