CVE-2024-10963

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Last Modified: UTC

Description

A flaw was found in pam_access, where certain rules in its configuration file are mistakenly treated as hostnames. This vulnerability allows attackers to trick the system by pretending to be a trusted hostname, gaining unauthorized access. This issue poses a risk for systems that rely on this feature to control who can access certain services or terminals.

A flaw was found in pam_access, where certain rules in its configuration file are mistakenly treated as hostnames. This vulnerability allows attackers to trick the system by pretending to be a trusted hostname, gaining unauthorized access. This issue poses a risk for systems that rely on this feature to control who can access certain services or terminals.

Statement

This vulnerability in pam_access is rated with an Important severity because it directly impacts the integrity of access control mechanisms in secure environments. By allowing hostname spoofing to bypass restrictions intended for specific local TTYs or services, the vulnerability enables attackers with minimal effort to exploit gaps in security policies that rely on access.conf configurations. The potential for unauthorized access is significant, as attackers with root privileges on any networked device can impersonate trusted service names to evade local access controls. This vulnerability was introduced in RHEL-9.4 and does not affect previous versions of RHEL-9.

This vulnerability in pam_access is rated with an Important severity because it directly impacts the integrity of access control mechanisms in secure environments. By allowing hostname spoofing to bypass restrictions intended for specific local TTYs or services, the vulnerability enables attackers with minimal effort to exploit gaps in security policies that rely on access.conf configurations. The potential for unauthorized access is significant, as attackers with root privileges on any networked device can impersonate trusted service names to evade local access controls.

This vulnerability was introduced in RHEL-9.4 and does not affect previous versions of RHEL-9.

Mitigation

To reduce the risk, administrators should ensure that no DNS hostname matches local TTY or service names used in pam_access. Additionally, implement DNSSEC to prevent spoofing of DNS responses. For stronger protection, consider reconfiguring pam_access to only accept fully qualified domain names (FQDNs) in access.conf

Additional information

  • Bugzilla 2324291: pam: Improper Hostname Interpretation in pam_access Leads to Access Control Bypass
  • CWE-287: Improper Authentication
  • FAQ: Frequently asked questions about CVE-2024-10963

Common Vulnerability Scoring System (CVSS) Score Details

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 HatNVD

CVSS v3 Base Score

7.4

N/A

Attack Vector

Network

N/A

Attack Complexity

High

N/A

Privileges Required

None

N/A

User Interaction

None

N/A

Scope

Unchanged

N/A

Confidentiality Impact

High

N/A

Integrity Impact

High

N/A

Availability Impact

None

N/A

CVSS v3 Vector

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

Understanding the Weakness (CWE)

CWE-287

Integrity,Confidentiality,Availability,Access Control

Technical Impact: Read Application Data; Gain Privileges or Assume Identity; Execute Unauthorized Code or Commands

This weakness can lead to the exposure of resources or functionality to unintended actors, possibly providing attackers with sensitive information or even execute arbitrary code.

Frequently Asked Questions

Why is Red Hat's CVSS v3 score or Impact different from other vendors?

My product is listed as "Under investigation" or "Affected", when will Red Hat release a fix for this vulnerability?

What can I do if my product is listed as "Will not fix"?

What can I do if my product is listed as "Fix deferred"?

What is a mitigation?

I have a Red Hat product but it is not in the above list, is it affected?

Why is my security scanner reporting my product as vulnerable to this vulnerability even though my product version is fixed or not affected?

My product is listed as "Out of Support Scope". What does this mean?

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