CVE-2026-104843
Description
A flaw was found in uv. An attacker could achieve arbitrary code execution on a Windows system by tricking a user into installing a specially crafted Python wheel package. During archive extraction, files can be written outside the intended target directory, allowing an attacker to place malicious executable files into locations within the system search path (PATH).
Statement
Red Hat rates this IMPORTANT vulnerability in uv, a Python package and project manager written in Rust, which is shipped in affected Red Hat offerings across AI and development-tools components. During installation of a Python wheel on Windows, uv could be induced by a maliciously crafted wheel to write files outside the intended installation directory, including placing an executable into a directory already present on the user's PATH. By tricking a user into installing such a wheel, an attacker could achieve arbitrary code execution in the context of that user when the planted executable is subsequently invoked, compromising the confidentiality, integrity, and availability of the user's account. Non-Windows hosts are not affected. The Red Hat severity of IMPORTANT (CVSS 3.1 score 7.8) differs from the upstream rating of MODERATE (CVSS 4.0 score 5.9) primarily because the upstream vector scores integrity-only impact requiring user interaction, while the Red Hat vector accounts for high impact to confidentiality, integrity, and availability within the user's security context.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. The upstream project reports no workaround other than upgrading; updating to uv 0.12.18 or later, which contains the fix, addresses the issue.
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 | 7.8 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | None | N/A | N/A |
| User Interaction | Required | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | High | N/A | N/A |
| Integrity Impact | High | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
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
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
