CVE-2021-30639

Description

A vulnerability in Apache Tomcat allows an attacker to remotely trigger a denial of service. An error introduced as part of a change to improve error handling during non-blocking I/O meant that the error flag associated with the Request object was not reset between requests. This meant that once a non-blocking I/O error occurred, all future requests handled by that request object would fail. Users were able to trigger non-blocking I/O errors, e.g. by dropping a connection, thereby creating the possibility of triggering a DoS. Applications that do not use non-blocking I/O are not exposed to this vulnerability. This issue affects Apache Tomcat 10.0.3 to 10.0.4; 9.0.44; 8.5.64.

CvssV3 impact

BaseSeverity

HIGH

ConfidentialityImpact

NONE

AttackComplexity

LOW

Scope

UNCHANGED

AttackVector

NETWORK

AvailabilityImpact

HIGH

IntegrityImpact

NONE

PrivilegesRequired

NONE

BaseScore

7.5

VectorString

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

Version

3.1

UserInteraction

NONE

CvssV2 impact

AccessComplexity

LOW

ConfidentialityImpact

NONE

AvailabilityImpact

PARTIAL

IntegrityImpact

NONE

BaseScore

5

VectorString

AV:N/AC:L/Au:N/C:N/I:N/A:P

Version

2.0

AccessVector

NETWORK

Authentication

NONE