CVE-2022-0778

Description

A flaw was found in OpenSSL. It is possible to trigger an infinite loop by crafting a certificate that has invalid elliptic curve parameters. Since certificate parsing happens before verification of the certificate signature, any process that parses an externally supplied certificate may be subject to a denial of service attack.

Statement

While Red Hat initially stated not to be directly affected by this flaw, after further investigation we found that the versions of OpenSSL as shipped in Red Hat Enterprise Linux 6, 7, and 8 are vulnerable to a denial of service attack through malicious Elliptic Curve parameters. During processing of the parameters OpenSSL will call BN_mod_sqrt() with invalid arguments, causing the process to enter an infinite loop. The invalid EC parameters can be provided to OpenSSL through X.509 certificates (used in TLS connections), through public and private keys, through certificate signing requests and other places where applications process Elliptic Curve parameters. The flaw has been rated as having a security impact of Important. A future update will address this issue in Red Hat Enterprise Linux 6, 7 and 8.

Mitigation

Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update the affected package as soon as possible.

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 Score7.57.57.5
Attack VectorNetworkNetworkNetwork
Attack ComplexityLowLowLow
Privileges RequiredNoneNoneNone
User InteractionNoneNoneNone
ScopeUnchangedUnchangedUnchanged
ConfidentialityNoneNoneNone
Integrity ImpactNoneNoneNone
Availability ImpactHighHighHigh

Vector

Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/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:N/I:N/A:H

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

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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