CVE-2019-9496

Description

From CVE.org

An invalid authentication sequence could result in the hostapd process terminating due to missing state validation steps when processing the SAE confirm message when in hostapd/AP mode. All version of hostapd with SAE support are vulnerable. An attacker may force the hostapd process to terminate, performing a denial of service attack. Both hostapd with SAE support and wpa_supplicant with SAE support prior to and including version 2.7 are affected.

Statement

Red Hat Enterprise Linux 5, 6, and 7 do not ship hostapd and they are not affected by this flaw.

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 Score6.57.5N/A
Attack VectorAdjacent NetworkNetworkN/A
Attack ComplexityLowLowN/A
Privileges RequiredNoneNoneN/A
User InteractionNoneNoneN/A
ScopeUnchangedUnchangedN/A
ConfidentialityNoneNoneN/A
Integrity ImpactNoneNoneN/A
Availability ImpactHighHighN/A

Vector

Red Hat: CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

NVD: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Understanding the Weakness (CWE)

Access Control

Technical Impact: Bypass Protection Mechanism; Gain Privileges or Assume Identity

An attacker could potentially modify the state in malicious ways. If the state is related to the privileges or level of authentication that the user has, then state modification might allow the user to bypass authentication or elevate privileges.

Confidentiality

Technical Impact: Read Application Data

The state variables may contain sensitive information that should not be known by the client.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

By modifying state variables, the attacker could violate the application's expectations for the contents of the state, leading to a denial of service due to an unexpected error condition.

Acknowledgements

Red Hat would like to thank Eyal Ronen (Tel Aviv University & KU Leuven) and Mathy Vanhoef (NYUAD) for reporting this issue.

Frequently Asked Questions

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