CVE-2026-27606
Description
A flaw was found in Rollup, a JavaScript module bundler. Insecure file name sanitization in the core engine allows an attacker to control output filenames, potentially through command-line interface (CLI) inputs, manual chunk aliases, or malicious plugins. By using directory traversal sequences (../), an attacker can overwrite files anywhere on the host filesystem where the build process has write permissions. This vulnerability can lead to persistent remote code execution (RCE) by overwriting critical system or user configuration files.
Statement
This is an Important vulnerability affecting Red Hat products that utilize the Rollup JavaScript module bundler. Insecure filename sanitization combined with unsafe path resolution allows an attacker to perform arbitrary file writes via path traversal. This enables the use of traversal sequences in output filenames, potentially leading to persistent Remote Code Execution by overwriting critical system or user configuration files.
Mitigation
To mitigate the risk of arbitrary file writes and remote code execution, ensure that build processes utilizing the Rollup module bundler are executed within a strictly controlled and isolated environment, such as a container with minimal privileges. Restrict the file system permissions of the user or service account running Rollup to only the directories absolutely necessary for its operation. Additionally, rigorously validate all inputs, including CLI arguments, manual chunk aliases, and third-party plugins, to prevent the introduction of malicious path traversal sequences.
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 | 9.1 | 9.8 | 9.1 |
| Attack Vector | Network | Network | Network |
| Attack Complexity | Low | Low | Low |
| Privileges Required | None | None | None |
| User Interaction | None | None | None |
| Scope | Unchanged | Unchanged | Unchanged |
| Confidentiality | High | High | High |
| Integrity Impact | High | High | High |
| Availability Impact | None | High | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
NVD: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/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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