Summary
HashiCorp go-slug Vulnerable to Zip Slip Attack
HashiCorp’s go-slug library is vulnerable to a zip-slip style attack when a non-existing user-provided path is extracted from the tar entry. This vulnerability, identified as CVE-2025-0377, is fixed in go-slug 0.16.3.
Background
HashiCorp’s go-slug shared library offers functions for packing and unpacking Terraform Enterprise compatible slugs. Slugs are gzip compressed tar files containing Terraform configuration files.
Details
When go-slug performs an extraction, the filename/extraction path is taken from the tar entry via the header.Name. It was discovered that the unpacking step improperly validated paths, potentially leading to path traversal, allowing an attacker to write an arbitrary file during extraction.
Impact
CVE-2025-0377 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (0.16.3); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Already deployed Kodem?
See it in your environmentNew to Kodem? Get a demo →Remediation advice
Consumers of the go-slug shared library should evaluate the risk associated with this issue in the context of their go-slug usage and upgrade go-slug to 0.16.3 or later.
Frequently Asked Questions
- What is CVE-2025-0377? CVE-2025-0377 is a high-severity security vulnerability in github.com/hashicorp/go-slug (go), affecting versions < 0.16.3. It is fixed in 0.16.3.
- How severe is CVE-2025-0377? CVE-2025-0377 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of github.com/hashicorp/go-slug are affected by CVE-2025-0377? github.com/hashicorp/go-slug (go) versions < 0.16.3 is affected.
- Is there a fix for CVE-2025-0377? Yes. CVE-2025-0377 is fixed in 0.16.3. Upgrade to this version or later.
- Is CVE-2025-0377 exploitable, and should I be worried? Whether CVE-2025-0377 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2025-0377 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2025-0377? Upgrade
github.com/hashicorp/go-slugto 0.16.3 or later.