Summary
A Path Traversal "Zip Slip" vulnerability has been identified in mholt/archiver in Go. This vulnerability allows using a crafted ZIP file containing path traversal symlinks to create or overwrite files with the user's privileges or application utilizing the library.
When using the archiver.Unarchive functionality with ZIP files, like this: archiver.Unarchive(zipFile, outputDir), A crafted ZIP file can be extracted in such a way that it writes files to the affected system with the same privileges as the application executing this vulnerable functionality. Consequently, sensitive files may be overwritten, potentially leading to privilege escalation, code execution, and other severe outcomes in some cases.
It's worth noting that a similar vulnerability was found in TAR files (CVE-2024-0406). Although a fix was implemented, it hasn't been officially released, and the affected project has since been deprecated. The successor to mholt/archiver is a new project called mholt/archives, and its initial release (v0.1.0) removes the Unarchive() functionality.
Impact
Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files. Typical impact: unauthorized file read or write outside the intended directory.
CVE-2025-3445 has a CVSS score of 8.1 (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. No fixed version is listed yet, so configuration controls and monitoring matter more in the interim.
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.
Remediation advice
In the interim: Resolve the canonical path after applying any user-supplied input, and verify it remains within the intended directory before accessing it.
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2025-3445? CVE-2025-3445 is a high-severity path traversal vulnerability in github.com/mholt/archiver (go), affecting versions <= 3.5.1. No fixed version is listed yet. Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files.
- How severe is CVE-2025-3445? CVE-2025-3445 has a CVSS score of 8.1 (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 packages are affected by CVE-2025-3445?
github.com/mholt/archiver(go) (versions <= 3.5.1)github.com/mholt/archiver/v3(go) (versions <= 3.5.1)
- Is there a fix for CVE-2025-3445? No fixed version is listed for CVE-2025-3445 yet. Monitor the advisory for updates and apply mitigations in the interim.
- Is CVE-2025-3445 exploitable, and should I be worried? Whether CVE-2025-3445 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-2025-3445 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-2025-3445? No fixed version is listed yet. In the interim: Resolve the canonical path after applying any user-supplied input, and verify it remains within the intended directory before accessing it.