CVE-2020-27955 — git-lfs
CRITICALCVE-2020-27955 is a critical-severity (CVSS 9.8) remote code execution vulnerability in github.com/git-lfs/git-lfs. 12 public exploit references exist, so weaponization risk is real. A fix is available for github.com/git-lfs/git-lfs — see the affected versions and patch details below.
Git LFS can execute a Git binary from the current directory
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2020-27955 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE sits: patch-first territory.
Where this sits among everything scored
Of 376,715 CVEs with a current EPSS score, this one falls in the 50–90% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/git-lfs/git-lfsReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Git LFS 2.12.0 allows Remote Code Execution.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/git-lfs/git-lfs | all versions | 2.12.1go get github.com/git-lfs/git-lfs@v2.12.1 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Git LFS 2.12.0 allows Remote Code Execution.
Git LFS 2.12.0 allows Remote Code Execution.
Git LFS 2.12.0 allows Remote Code Execution.
Git LFS 2.12.0 allows Remote Code Execution.
Git LFS 2.12.0 allows Remote Code Execution.
Git LFS 2.12.0 allows Remote Code Execution.
Git LFS 2.12.0 allows Remote Code Execution.
Git LFS 2.12.0 allows Remote Code Execution.
Git LFS 2.12.0 allows Remote Code Execution.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/git-lfs/git-lfs, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/git-lfs/git-lfs to 2.12.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-27955 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2020-27955 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2020-27955. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2020-27955 in your dependencies?
O3 Security finds CVE-2020-27955 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.