CVE-2023-27539

Description

A denial of service vulnerability was found in rubygem-rack in how it parses headers. A carefully crafted input can cause header parsing to take an unexpected amount of time, possibly resulting in a denial of service.

Mitigation

Setting Regexp.timeout in Ruby 3.2 is a possible workaround.

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 Score5.35.35.3
Attack VectorNetworkNetworkNetwork
Attack ComplexityLowLowLow
Privileges RequiredNoneNoneNone
User InteractionNoneNoneNone
ScopeUnchangedUnchangedUnchanged
ConfidentialityNoneNoneLow
Integrity ImpactNoneNoneNone
Availability ImpactLowLowNone

Vector

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

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

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

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Resource Consumption (CPU)

Attackers can create crafted inputs that intentionally cause the regular expression to use excessive backtracking in a way that causes the CPU consumption to spike.

Frequently Asked Questions

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