CVE-2023-34236
HIGHInformation Disclosure Vulnerability in Weave GitOps Terraform Controller
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.
Blast Radius
github.com/weaveworks/tf-controller🐹github.com/weaveworks/tf-controllerReal-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
Weave GitOps Terraform Controller (aka Weave TF-controller) is a controller for Flux to reconcile Terraform resources in a GitOps way. A vulnerability has been identified in Weave GitOps Terraform Controller which could allow an authenticated remote attacker to view sensitive information. This vulnerability stems from Weave GitOps Terraform Runners (tf-runner), where sensitive data is inadvertently printed - potentially revealing sensitive user data in their pod logs. In particular, functions tfexec.ShowPlan, tfexec.ShowPlanRaw, and tfexec.Output are implicated when the tfexec object set its Stdout and Stderr to be os.Stdout and os.Stderr. An unauthorized remote attacker could exploit this vulnerability by accessing these prints of sensitive information, which may contain configurations or tokens that could be used to gain unauthorized control or access to resources managed by the Terraform controller. A successful exploit could allow the attacker to utilize this sensitive data, potentially leading to unauthorized access or control of the system. This vulnerability has been addressed in Weave GitOps Terraform Controller versions v0.14.4 and v0.15.0-rc.5. Users are urged to upgrade to one of these versions to mitigate the vulnerability. As a temporary measure until the patch can be applied, users can add the environment variable DISABLE_TF_LOGS to the tf-runners via the runner pod template of the Terraform Custom Resource. This will prevent the logging of sensitive information and mitigate the risk of this vulnerability.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/weaveworks/tf-controller | all versions | 0.14.4 |
| 🐹Go | github.com/weaveworks/tf-controller | ≥ 0.15.0-rc.1&&< 0.15.0-rc.5 | 0.15.0-rc.5 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/weaveworks/tf-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/weaveworks/tf-controller to 0.14.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-34236 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 CVE-2023-34236 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 CVE-2023-34236. 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-2023-34236 in your dependencies?
O3 detects CVE-2023-34236 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.