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

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.

Published: 2021-01-15 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-21237 is rated Moderate Risk (43.6/100): CVSS High severity, with low exploitation likelihood (EPSS 0.20%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-21237

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-11-21 0.08% 0.20% +0.12%
2 2025-11-18 0.20% 0.08% -0.12%
3 2025-03-30 0.20%

Full EPSS history (11 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-21237

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.2 3.1 HIGH
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
0.8 5.8 [email protected]
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 5.9 [email protected]
4.6 2.0 MEDIUM
AV:L/AC:L/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
3.9 6.4 [email protected]

Weakness enumeration for CVE-2021-21237

GitHub Security Advisory for CVE-2021-21237

GHSA-cx3w-xqmc-84g5 · Severity: high · Ecosystem: go — Git LFS can execute a Git binary from the current directory on Windows

OS Trackers for CVE-2021-21237

vendor priority summary link
debian unimportant CVE-2021-21237 unimportant priority: Debian including 1 source packages (git-lfs), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2021-21237
ubuntu medium CVE-2021-21237 medium priority: Ubuntu including 1 source packages (git-lfs), 16 status rows across 16 suites (bionic, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 12, DNE 2, ignored 1, released 1. https://ubuntu.com/security/CVE-2021-21237

Affected software / configurations for CVE-2021-21237

Vendor Product Version Raw CPE
git_large_file_storage_project git_large_file_storage < 2.13.2 cpe:2.3:a:git_large_file_storage_project:git_large_file_storage:*:*:*:*:*:*:*:*

References for CVE-2021-21237

cvelogic Threat Intelligence