Vulnerability in github.com/gruntwork-io/terragrunt (CVE-2026-64672)

Summary

Vulnerability in github.com/gruntwork-io/terragrunt (CVE-2026-64672). Risk of unauthorized operations or information disclosure. Exploitable via TMPDIR. Mitigation: upgrade to 1.1.1 or later.

Original description

The description as published by the source.

Summary

Terragrunt's terragrunt catalog command clones each repository referenced in your catalog configuration into a temporary working directory. In affected versions, the clone path it derived was deterministic and sat under the shared system temporary directory, in the form /catalog-. Because that path was predictable and Terragrunt followed a symlink already present there instead of rejecting it, a local attacker could plant a symlink at that path and cause Terragrunt to delete a directory and re-clone into it outside the intended temporary root.

Impact

This affected users who ran terragrunt catalog on a host they shared with other local users or processes they did not fully trust, such as a multi-user server or a shared CI runner. The attack required a local attacker: a separate local user or process able to write to the shared system temporary directory. It was not remotely exploitable, and the victim had to run terragrunt catalog while the attacker's symlink was already in place.

Because the predictable path depended only on the repository URL being cataloged and the location of the system temporary directory, the attacker could compute it in advance and plant a symlink there before the victim ran the command. When the victim ran terragrunt catalog, Terragrunt followed the symlink out of the intended temporary root, deleted an existing `` directory under the attacker-chosen parent, and repopulated that path with the cloned repository contents. Al…

Source: GitHub Security Advisories (Global) NVD GitHub Advisory

Auto-generated summary

Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.

A vulnerability tracked as CVE-2026-64672 has been found in github.com/gruntwork-io/terragrunt.
Attackers can target a specific entry point like TMPDIR over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade github.com/gruntwork-io/terragrunt to 1.1.1 or later.
If unsure, ask your IT team or search "github.com/gruntwork-io/terragrunt CVE-2026-64672" on the vendor's site.

CVE-2026-64672 (github.com/gruntwork-io/terragrunt) — CWE-59
Attack surface: TMPDIR / TMP / TEMP
Patched: 1.1.1 — apply immediately
Workaround: If you cannot upgrade immediately, ensure that you do not allow untrusted parties to control the values of TMPDIR, TMP, and TEMP in environments where you run terragrunt catalog.
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.

❓ What is the problem

A vulnerability (CWE-59) exists in github.com/gruntwork-io/terragrunt. Attackers reach the vulnerable code path via TMPDIR.

📍 Affected scope

Check the vendor advisory for the affected versions of github.com/gruntwork-io/terragrunt. Attack surface: TMPDIR / TMP / TEMP.

🔥 Severity

Severity: ?. Risk of unauthorized operations or information disclosure.

🔧 How to fix

Update to 1.1.1.

🛡️ Workaround

Workaround: If you cannot upgrade immediately, ensure that you do not allow untrusted parties to control the values of TMPDIR, TMP, and TEMP in environments where you run terragrunt catalog.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'github.com/gruntwork-io/terragrunt' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.

Response actions

Concrete steps and command examples for SOC/SRE teams to execute in order

1
Identify exposure identify
```
grep -r 'github.com/gruntwork-io/terragrunt' . | grep -v node_modules
```
リポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で github.com/gruntwork-io/terragrunt を grep し、稼働しているサービス・バージョンを把握する。
2
Apply temporary workaround mitigate
```
If you cannot upgrade immediately, ensure that you do not allow untrusted parties to control the values of `TMPDIR`, `TMP`, and `TEMP` in environments where you run `terragrunt catalog`.
```
パッチが適用されるまでの応急処置として、If you cannot upgrade immediately, ensure that you do not allow untrusted parties to control the values of TMPDIR, TMP, and TEMP in environments where you run terragrunt catalog. を実施。回避策の副作用 (機能低下) を確認した上で。
3
Apply patch patch
```
Upgrade github.com/gruntwork-io/terragrunt to 1.1.1
```
ステージング環境で 1.1.1 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
4
Post-deployment verification verify
```
Confirm patched version is live in production
```
パッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。

Affected packages

go github.com/gruntwork-io/terragrunt

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.1.1"}]}]

Summary

Original description

Summary

Impact

Auto-generated summary

Response actions

Affected packages

References