CVE-2024-2511

Description

A flaw was found in OpenSSL. A malicious client can trigger an uncontrolled memory consumption, resulting in a Denial of Service. This issue occurs due to OpenSSL's TLSv1.3 session cache going into an incorrect state, leading to it failing to flush properly as it fills. OpenSSL must be configured with the non-default SSL_OP_NO_TICKET option enabled to be vulnerable. This issue only affects TLSv1.3 servers, while TLS clients are not affected.

Statement

The OpenSSL version shipped with Red Hat Enterprise Linux 7 is not affected by this issue, as the version 1.0.2 does not contain the related bug.

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).

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score3.7N/A5.9
Attack VectorNetworkN/ANetwork
Attack ComplexityHighN/AHigh
Privileges RequiredNoneN/ANone
User InteractionNoneN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityNoneN/ANone
Integrity ImpactNoneN/ANone
Availability ImpactLowN/AHigh

Vector

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

cve.org: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)

If an attacker can trigger the allocation of the limited resources, but the number or size of the resources is not controlled, then the most common result is denial of service. This would prevent valid users from accessing the product, and it could potentially have an impact on the surrounding environment, i.e., the product may slow down, crash due to unhandled errors, or lock out legitimate users. For example, a memory exhaustion attack against an application could slow down the application as well as its host operating system.

Access Control,Other

Technical Impact: Bypass Protection Mechanism; Other

In some cases it may be possible to force the product to "fail open" in the event of resource exhaustion. The state of the product -- and possibly the security functionality - may then be compromised.

Frequently Asked Questions

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