How severe is GHSA-j77r-2fxf-5jrw?

GHSA-j77r-2fxf-5jrw has a CVSS score of 9.9/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by GHSA-j77r-2fxf-5jrw?

GHSA-j77r-2fxf-5jrw affects the following packages: github.com/fluxcd/kustomize-controller (Go), github.com/fluxcd/flux2 (Go). Ecosystems affected: Go.

How do I fix GHSA-j77r-2fxf-5jrw?

Update github.com/fluxcd/kustomize-controller to 0.24.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-j77r-2fxf-5jrw is resolved across your whole dependency graph.

How do I detect GHSA-j77r-2fxf-5jrw in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/fluxcd/kustomize-controller. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate GHSA-j77r-2fxf-5jrw if there is no patch (or I can't update yet)?

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 does O3 Security protect against GHSA-j77r-2fxf-5jrw?

O3 pinpoints whether GHSA-j77r-2fxf-5jrw is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-j77r-2fxf-5jrw actively exploited in the wild?

No public exploit code has been indexed for GHSA-j77r-2fxf-5jrw yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-j77r-2fxf-5jrw?

GHSA-j77r-2fxf-5jrw has an EPSS (Exploit Prediction Scoring System) score of 1.1%, placing it in the 61th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-j77r-2fxf-5jrw?

GHSA-j77r-2fxf-5jrw is classified as Path Traversal (CWE-22), CWE-36 (CWE-36). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was GHSA-j77r-2fxf-5jrw published, and has it been updated?

GHSA-j77r-2fxf-5jrw was published on May 4, 2022 and was last updated on February 4, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

GHSA-j77r-2fxf-5jrw: kustomize-controller Privilege Escalation…

EPSS Exploitation Probability

via FIRST.org ↗

1.1%probability of exploitation in next 30 days

Lower Risk61th percentile+0.47%

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.

Blast Radius

2 pkgs affected

🐹github.com/fluxcd/kustomize-controller🐹github.com/fluxcd/flux2

Real-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

The kustomize-controller enables the use of Kustomize’s functionality when applying Kubernetes declarative state onto a cluster. A malicious user can use built-in features and a specially crafted kustomization.yaml to expose sensitive data from the controller’s pod filesystem. In multi-tenancy deployments this can lead to privilege escalation if the controller's service account has elevated permissions.

Within the affected versions, users with write access to a Flux source are able to use built-in features to expose sensitive data from the controller’s pod filesystem using a malicious kustomization.yaml file.

This vulnerability was fixed in kustomize-controller v0.24.0 and included in flux2 v0.29.0 released on 2022-04-20. The changes introduce a new Kustomize file system implementation which ensures that all files being handled are contained within the Kustomization working directory, blocking references to any files that do not meet that requirement.

Automated tooling (e.g. conftest) could be employed as a workaround, as part of a user's CI/CD pipeline to ensure that their kustomization.yaml files conform with specific policies, blocking access to sensitive path locations.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/fluxcd/kustomize-controller`	all versions	0.24.0
🐹Go	`github.com/fluxcd/flux2`	all versions	0.29.0

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/fluxcd/kustomize-controller. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/fluxcd/kustomize-controller to 0.24.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-j77r-2fxf-5jrw 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 pinpoints whether GHSA-j77r-2fxf-5jrw is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-j77r-2fxf-5jrw. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

The kustomize-controller enables the use of Kustomize’s functionality when applying Kubernetes declarative state onto a cluster. A malicious user can use built-in features and a specially crafted `kustomization.yaml` to expose sensitive data from the controller’s pod filesystem. In multi-tenancy deployments this can lead to privilege escalation if the controller's service account has elevated permissions. Within the affected versions, users with write access to a Flux source are able to use built-in features to expose sensitive data from the controller’s pod filesystem using a malicious `kust

O3 Security · Impact-Aware SCA

Is GHSA-j77r-2fxf-5jrw in your dependencies?

O3 detects GHSA-j77r-2fxf-5jrw across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works

GHSA-j77r-2fxf-5jrw