CVE-2024-37371

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ModerateModerate ImpactWhat does this mean?
DescriptionStatementMitigationAdditional informationCVSS Score DetailsFAQ

Description

A vulnerability was found in the MIT Kerberos 5 GSS krb5 wrap token, where an attacker can modify the plaintext Extra Count field, causing the unwrapped token to appear truncated to the application, occurs when the attacker alters the token data during transmission which can lead to improper handling of authentication tokens.

A vulnerability was found in the MIT Kerberos 5 GSS krb5 wrap token, where an attacker can modify the plaintext Extra Count field, causing the unwrapped token to appear truncated to the application, occurs when the attacker alters the token data during transmission which can lead to improper handling of authentication tokens.

Statement

This issue is classified as a moderate severity vulnerability because, while it allows an attacker to modify the plaintext "Extra Count" field of a GSS krb5 wrap token, the impact is primarily limited to token truncation at the application layer. This truncation can disrupt services but does not directly lead to a full compromise of confidentiality or integrity. The attack requires that the attacker already has access to a valid token transmission to modify, meaning it cannot be exploited remotely without first obtaining or intercepting a valid token.

This issue is classified as a moderate severity vulnerability because, while it allows an attacker to modify the plaintext "Extra Count" field of a GSS krb5 wrap token, the impact is primarily limited to token truncation at the application layer. This truncation can disrupt services but does not directly lead to a full compromise of confidentiality or integrity. The attack requires that the attacker already has access to a valid token transmission to modify, meaning it cannot be exploited remotely without first obtaining or intercepting a valid token.

Mitigation

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

Additional information

  • Bugzilla 2294676: krb5: GSS message token handling
  • FAQ: Frequently asked questions about CVE-2024-37371

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

6.5

9.1

Attack Vector

Network

Network

Attack Complexity

Low

Low

Privileges Required

Low

None

User Interaction

None

None

Scope

Unchanged

Unchanged

Confidentiality Impact

None

High

Integrity Impact

None

None

Availability Impact

High

High

CVSS v3 Vector

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

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

Red Hat CVSS v3 Score Explanation

The attacker must have some level of access to an ongoing communication session, specifically to observe or modify valid tokens during transmission. However, they do not need elevated privileges such as administrative or system-level access to exploit the vulnerability. The attacker only needs user-level access to intercept or manipulate tokens, so Privileges Required is Low. Also the vulnerability does not expose any sensitive information or compromise the confidentiality of the communication. The attack affects the integrity of the token by making it appear truncated, but it does not result in the disclosure of the underlying token contents or any confidential data. As a result, there is no direct impact on confidentiality, justifying the "None" rating for this metric.

The attacker must have some level of access to an ongoing communication session, specifically to observe or modify valid tokens during transmission. However, they do not need elevated privileges such as administrative or system-level access to exploit the vulnerability. The attacker only needs user-level access to intercept or manipulate tokens, so Privileges Required is Low.

Also the vulnerability does not expose any sensitive information or compromise the confidentiality of the communication. The attack affects the integrity of the token by making it appear truncated, but it does not result in the disclosure of the underlying token contents or any confidential data. As a result, there is no direct impact on confidentiality, justifying the "None" rating for this metric.

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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