CVE-2022-48566

Description

A constant-time-defeating optimization issue was found in python. This issue occurs when sending a specially crafted request, which could allow an attacker to obtain sensitive information.

Statement

This flaw is classified as Moderate as in contrast to an Important rating, the exploitation of this vulnerability is difficult to achieve and the outcome of the impact is breach of confidentiality.

Versions of python36:3.6/python36 as shipped with Red Hat Enterprise Linux 8 are marked as 'Not affected' as they just provide "symlinks" to the main python3 component, which provides the interpreter of the Python programming language.

Versions of python39:3.9/python39 and python2 in various modules as shipped with Red Hat Enterprise Linux 8, python3.11/python3.9 as shipped with Red Hat Enterprise Linux 9 and python 3.8.14 as shipped with Red Hat Software Collections are marked as 'Not affected' as they are higher than the vulnerable version, thereby containing the fixed code.

Mitigation

As per upstream, either make the accumulator variable result a volatile unsigned char instead of unsigned char or use instead use CRYPTO_memcmp from OpenSSL/BoringSSL when SSL is available as SSL libraries are more secure when it comes to timing based vulnerabilities.

https://github.com/python/cpython/issues/84968

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 Score5.95.9N/A
Attack VectorNetworkNetworkN/A
Attack ComplexityHighHighN/A
Privileges RequiredNoneNoneN/A
User InteractionNoneNoneN/A
ScopeUnchangedUnchangedN/A
ConfidentialityHighHighN/A
Integrity ImpactNoneNoneN/A
Availability ImpactNoneNoneN/A

Vector

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

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

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)

When a race condition makes it possible to bypass a resource cleanup routine or trigger multiple initialization routines, it may lead to resource exhaustion.

Availability

Technical Impact: DoS: Crash, Exit, or Restart; DoS: Instability

When a race condition allows multiple control flows to access a resource simultaneously, it might lead the product(s) into unexpected states, possibly resulting in a crash.

Confidentiality,Integrity

Technical Impact: Read Files or Directories; Read Application Data

When a race condition is combined with predictable resource names and loose permissions, it may be possible for an attacker to overwrite or access confidential data (CWE-59).

Access Control

Technical Impact: Execute Unauthorized Code or Commands; Gain Privileges or Assume Identity; Bypass Protection Mechanism

This can have security implications when the expected synchronization is in security-critical code, such as recording whether a user is authenticated or modifying important state information that should not be influenced by an outsider.

Frequently Asked Questions

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