CVE-2026-71556 is a high-severity (CVSS 7.1) CWE-59 vulnerability in github.com/go-git/go-git/v5. A fix is available for github.com/go-git/go-git/v5 — see the affected versions and patch details below.
go-git: Worktree operations may follow symlinks
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-71556.
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-2026-71556 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,333 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/go-git/go-git/v5🐹github.com/go-git/go-git/v6Real-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
Impact
A symlink traversal issue in go-git could allow worktree operations to modify files outside the intended worktree path.
The worktreeFilesystem wrapper rejected dangerous path strings, including paths containing .git, parent-directory components, or control characters. However, it did not prevent filesystem operations from following symbolic links that were already present in the worktree.
As a result, a path that is safe when evaluated as a string could still resolve into the repository's Git metadata directory. For example, if s is a symbolic link to .git, writing to s/config would modify .git/config.
A symbolic link at the final path component could also be followed. For example, if s points directly to .git/config, opening s for writing with truncation could overwrite the repository configuration.
Exploitation requires an attacker to be able to introduce or control a symbolic link in the worktree and cause the application to perform a write through that path.
Applications using storage/memory for their Storer, or go-billy/memfs for their Worktree, are not affected by this vulnerability.
Patches
The issue has been addressed by making the worktree filesystem wrapper a symlink-safe boundary.
Worktree operations now reject paths where an existing symbolic link in any path component could cause the operation to escape the intended worktree location, including symbolic links at the final component.
Users of filesystem-backed worktrees should upgrade to a patched version.
Credits
Thanks to @kodareef5 for reporting this issue and working with the go-git security team toward its resolution. :1st_place_medal: We would also like to thank @HughLewis20, who independently reported the same issue while a fix was already in progress.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/go-git/go-git/v5 | all versions | 5.19.2go get github.com/go-git/go-git/v5@v5.19.2 |
| 🐹Go | github.com/go-git/go-git/v6 | all versions | 6.0.0-alpha.5go get github.com/go-git/go-git/v6@v6.0.0-alpha.5 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/go-git/go-git/v5, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/go-git/go-git/v5 to 5.19.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-71556 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-2026-71556 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-71556. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
go-git is a pure-Go implementation of Git. During worktree operations (checkout, status, add), go-git resolves symbolic links without confining resolution to the worktree boundary, so a maliciously crafted repository containing a symlink can cause a consuming application to read from or write to files outside the…
| Product | Fixed in | Advisory |
|---|---|---|
| RHEM 1.1 for RHEL 10 | flightctl-0:1.1.4-1.el10em | RHSA-2026:68334 |
| RHEM 1.2 for RHEL 10 | flightctl-0:1.2.1-1.el10 | RHSA-2026:68335 |
| external secrets operator for Red Hat OpenShift 1.2 | external-secrets-operator/external-secrets-rhel9:1788963929 | RHSA-2026:66363 |
| Red Hat Advanced Cluster Management for Kubernetes 2.11 | rhacm2/multicluster-operators-subscription-rhel9:1788976330 | RHSA-2026:67538 |
| Red Hat Advanced Cluster Management for Kubernetes 2.13 | rhacm2/multicluster-operators-subscription-rhel9:1788977270 | RHSA-2026:67540 |
| Red Hat Advanced Cluster Management for Kubernetes 2.14 | rhacm2/multicluster-operators-subscription-rhel9:1788976403 | RHSA-2026:67539 |
| Red Hat Advanced Cluster Management for Kubernetes 2.15 | rhacm2/multicluster-operators-subscription-rhel9:1788976524 | RHSA-2026:67541 |
| Red Hat Advanced Cluster Management for Kubernetes 2.16 | rhacm2/multicluster-operators-subscription-rhel9:1788976747 | RHSA-2026:67542 |
Frequently Asked Questions
Is CVE-2026-71556 in your dependencies?
O3 Security finds CVE-2026-71556 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.