CVE-2022-41720

Description

A flaw was found in OS, net/http golang library. In Windows, restricted files can be accessed via os.DirFS and http.Dir. The os.DirFS function and http.Dir type provide access to a tree of files rooted in a given directory. These functions permit access to Windows device files under that root. For example, os.DirFS("C:/tmp").Open("COM1") opens the COM1 device. Both os.DirFS and http.Dir only provide read-only filesystem access. In addition, on Windows, an os.DirFS for the directory (the root of the current drive) can permit a maliciously crafted path to escape from the drive and access any path on the system. With the fix applied, the behavior of os.DirFS("") has changed. Previously, an empty root was treated equivalently to "/", so os.DirFS("").Open("tmp") would open the path "/tmp". This now returns an error.

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).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score7.57.57.5
Attack VectorNetworkNetworkNetwork
Attack ComplexityLowLowLow
Privileges RequiredNoneNoneNone
User InteractionNoneNoneNone
ScopeUnchangedUnchangedUnchanged
ConfidentialityHighHighHigh
Integrity ImpactNoneNoneNone
Availability ImpactNoneNoneNone

Vector

Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

NVD: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/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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