CVE-2021-33642

Description

From CVE.org

When a file is processed, an infinite loop occurs in next_inline() of the more_curly() function.

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).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score3.35.5N/A
Attack VectorLocalLocalN/A
Attack ComplexityLowLowN/A
Privileges RequiredNoneNoneN/A
User InteractionRequiredRequiredN/A
ScopeUnchangedUnchangedN/A
ConfidentialityNoneNoneN/A
Integrity ImpactNoneNoneN/A
Availability ImpactLowHighN/A

Vector

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

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

Red Hat CVSS v3 Score Explanation

byacc is not a network facing service, so a network attack vector does not make sense at all. If the argument is that it can be invoked by a network service then that's the responsibility of the service invoking byacc to sanitize inputs to it.

By being a standalone program, byacc is not designed to accept untrusted inputs over the network, much like cp, ls, etc. As a result, the only plausible security consequence byacc can cause is an escalation of privileges and these bugs don't do that; byacc is not a setuid program either.

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Amplification

An infinite loop will cause unexpected consumption of resources, such as CPU cycles or memory. The software's operation may slow down, or cause a long time to respond.

Frequently Asked Questions

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