CVE-2024-10963

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ImportantImportant ImpactWhat does this mean?
DescriptionStatementMitigationAdditional informationCVSS Score DetailsWeakness (CWE)FAQ

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

Frequently Asked Questions

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

For open source software shipped by multiple vendors, the CVSS base scores may vary for each vendor's version depending on the version they ship, how they ship it, the platform, and even how the software is compiled. This makes scoring of vulnerabilities difficult for third-party vulnerability databases such as NVD that only provide a single CVSS base score for each vulnerability. Red Hat scores reflect how a vulnerability affects our products specifically.

For more information, see https://access.redhat.com/solutions/762393.

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

  • "Under investigation" doesn't necessarily mean that the product is affected by this vulnerability. It only means that our Analysis Team is still working on determining whether the product is affected and how it is affected.
  • "Affected" means that our Analysis Team has determined that this product is affected by this vulnerability and might release a fix to address this in the near future.

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

A "will not fix" status means that a fix for an affected product version is not planned or not possible due to complexity, which may create additional risk.

Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
  • Upgrade to a supported product version that includes a fix for this vulnerability (recommended).
  • Apply a mitigation (if one exists).
  • Open a support case to request a prioritization of releasing a fix for this vulnerability.

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

A deferred status means that a fix for an affected product version is not guaranteed due to higher-priority development work.

Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
  • Apply a mitigation (if one exists).
  • Open a support case to request a prioritization of releasing a fix for this vulnerability.
  • Red Hat Engineering focuses on addressing high-priority issues based on their complexity or limited lifecycle support. Therefore, lower-priority issues will not receive immediate fixes.

What is a mitigation?

A mitigation is an action that can be taken to reduce the impact of a security vulnerability, without deploying any fixes.

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

The listed products were found to include one or more of the components that this vulnerability affects. These products underwent a thorough evaluation to determine their affectedness by this vulnerability. Note that layered products (such as container-based offerings) that consume affected components from any of the products listed in this table may be affected and are not represented.

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

In order to maintain code stability and compatibility, Red Hat usually does not rebase packages to entirely new versions. Instead, we backport fixes and new features to an older version of the package we distribute. This can result in some security scanners that only consider the package version to report the package as vulnerable. To avoid this, we suggest that you use an approved vulnerability scanner from our Red Hat Vulnerability Scanner Certification program.

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