CVE-2026-56876
Description
A flaw was found in extract-zip. This vulnerability allows a remote attacker to craft a malicious zip file containing symbolic links that point to locations outside the intended extraction directory. When a user extracts this malicious archive, extract-zip fails to validate the symlink targets, leading to the creation of files in arbitrary locations on the system. This could enable an attacker to read or write to sensitive files, potentially leading to information disclosure or system compromise.
Statement
A flaw was found in the extract-zip npm package. The package does not validate symlink targets when extracting ZIP archives. When processing a malicious ZIP file containing a symlink with a relative path (e.g., '../../../../etc/passwd'), extract-zip extracts the symlink without validation, allowing it to point outside the intended extraction directory. Depending on how extract-zip is used, an attacker could read arbitrary files (information disclosure) or write to arbitrary locations (arbitrary file write) on the system. Exploitation requires a user or automated process to extract a crafted ZIP archive.
Mitigation
No patch is available for extract-zip. The upstream maintainer is unresponsive (last commit 4+ years ago), and no fix is expected. Users should avoid using this package to extract untrusted ZIP archives.
As a workaround, validate symlink targets manually before extraction, use an alternative library such as adm-zip or yauzl with proper path validation, or run extraction in a sandboxed environment (container, isolated filesystem).
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 8.1 | N/A | 8.1 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | Required | N/A | Required |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | High | N/A | High |
| Availability Impact | None | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
Understanding the Weakness (CWE)
Integrity,Confidentiality,Availability
Technical Impact: Execute Unauthorized Code or Commands
The attacker may be able to create or overwrite critical files that are used to execute code, such as programs or libraries.
Integrity
Technical Impact: Modify Files or Directories
The attacker may be able to overwrite or create critical files, such as programs, libraries, or important data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, appending a new account at the end of a password file may allow an attacker to bypass authentication.
Confidentiality
Technical Impact: Read Files or Directories
The attacker may be able read the contents of unexpected files and expose sensitive data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, by reading a password file, the attacker could conduct brute force password guessing attacks in order to break into an account on the system.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
The attacker may be able to overwrite, delete, or corrupt unexpected critical files such as programs, libraries, or important data. This may prevent the product from working at all and in the case of protection mechanisms such as authentication, it has the potential to lock out product users.
Frequently Asked Questions
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