CVE-2021-30639

DoS after non-blocking IO error

Severity Score

7.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

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.

Una vulnerabilidad en Apache Tomcat permite a un atacante desencadenar remotamente una denegación de servicio. Un error introducido como parte de un cambio para mejorar el manejo de errores durante la I/O sin bloqueo significaba que el flag de error asociado al objeto Request no se restablecía entre peticiones. Esto significaba que una vez que se producía un error de I/O sin bloqueo, todas las futuras peticiones manejadas por ese objeto de petición podrían producir un fallo. Unos usuarios podían desencadenar errores de I/O sin bloqueo, por ejemplo, abandonando una conexión, creando así la posibilidad de desencadenar una DoS. Las aplicaciones que no usan I/O sin bloqueo no están expuestas a esta vulnerabilidad. Este problema afecta a Apache Tomcat versiones 10.0.3 a 10.0.4; 9.0.44; 8.5.64

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Network

Attack Complexity

Low

Authentication

None

Confidentiality

None

Integrity

None

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2021-04-13 CVE Reserved
2021-07-12 CVE Published
2024-08-03 CVE Updated
2024-08-28 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-755: Improper Handling of Exceptional Conditions

CAPEC

References (7)

URL	Tag	Source
https://kc.mcafee.com/corporate/index?page=content&id=SB10366	Third Party Advisory
https://lists.apache.org/thread.html/r79a7c019712b39aedf7cf4da9276d80610f04441b2a4f6506cb2daaf%40%3Cdev.tomcat.apache.org%3E	Mailing List
https://lists.apache.org/thread.html/r79a7c019712b39aedf7cf4da9276d80610f04441b2a4f6506cb2daaf%40%3Cusers.tomcat.apache.org%3E	Mailing List
https://security.netapp.com/advisory/ntap-20210827-0007	Third Party Advisory

URL	Date	SRC

URL	Date	SRC
https://www.oracle.com/security-alerts/cpujan2022.html	2023-11-07

URL	Date	SRC
https://lists.apache.org/thread.html/rd84fae1f474597bdf358f5bdc0a5c453c507bd527b83e8be6b5ea3f4%40%3Cannounce.tomcat.apache.org%3E	2023-11-07
https://security.gentoo.org/glsa/202208-34	2023-11-07

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Apache Search vendor "Apache"		Tomcat Search vendor "Apache" for product "Tomcat"				8.5.64 Search vendor "Apache" for product "Tomcat" and version "8.5.64"		-		Affected
Apache Search vendor "Apache"		Tomcat Search vendor "Apache" for product "Tomcat"				9.0.44 Search vendor "Apache" for product "Tomcat" and version "9.0.44"		-		Affected
Apache Search vendor "Apache"		Tomcat Search vendor "Apache" for product "Tomcat"				10.0.3 Search vendor "Apache" for product "Tomcat" and version "10.0.3"		-		Affected
Apache Search vendor "Apache"		Tomcat Search vendor "Apache" for product "Tomcat"				10.0.4 Search vendor "Apache" for product "Tomcat" and version "10.0.4"		-		Affected
Mcafee Search vendor "Mcafee"		Epolicy Orchestrator Search vendor "Mcafee" for product "Epolicy Orchestrator"				< 5.10.0 Search vendor "Mcafee" for product "Epolicy Orchestrator" and version " < 5.10.0"		-		Affected
Mcafee Search vendor "Mcafee"		Epolicy Orchestrator Search vendor "Mcafee" for product "Epolicy Orchestrator"				5.10.0 Search vendor "Mcafee" for product "Epolicy Orchestrator" and version "5.10.0"		-		Affected
Mcafee Search vendor "Mcafee"		Epolicy Orchestrator Search vendor "Mcafee" for product "Epolicy Orchestrator"				5.10.0 Search vendor "Mcafee" for product "Epolicy Orchestrator" and version "5.10.0"		update_1		Affected
Mcafee Search vendor "Mcafee"		Epolicy Orchestrator Search vendor "Mcafee" for product "Epolicy Orchestrator"				5.10.0 Search vendor "Mcafee" for product "Epolicy Orchestrator" and version "5.10.0"		update_10		Affected
Mcafee Search vendor "Mcafee"		Epolicy Orchestrator Search vendor "Mcafee" for product "Epolicy Orchestrator"				5.10.0 Search vendor "Mcafee" for product "Epolicy Orchestrator" and version "5.10.0"		update_2		Affected
Mcafee Search vendor "Mcafee"		Epolicy Orchestrator Search vendor "Mcafee" for product "Epolicy Orchestrator"				5.10.0 Search vendor "Mcafee" for product "Epolicy Orchestrator" and version "5.10.0"		update_3		Affected
Mcafee Search vendor "Mcafee"		Epolicy Orchestrator Search vendor "Mcafee" for product "Epolicy Orchestrator"				5.10.0 Search vendor "Mcafee" for product "Epolicy Orchestrator" and version "5.10.0"		update_4		Affected
Mcafee Search vendor "Mcafee"		Epolicy Orchestrator Search vendor "Mcafee" for product "Epolicy Orchestrator"				5.10.0 Search vendor "Mcafee" for product "Epolicy Orchestrator" and version "5.10.0"		update_5		Affected
Mcafee Search vendor "Mcafee"		Epolicy Orchestrator Search vendor "Mcafee" for product "Epolicy Orchestrator"				5.10.0 Search vendor "Mcafee" for product "Epolicy Orchestrator" and version "5.10.0"		update_6		Affected
Mcafee Search vendor "Mcafee"		Epolicy Orchestrator Search vendor "Mcafee" for product "Epolicy Orchestrator"				5.10.0 Search vendor "Mcafee" for product "Epolicy Orchestrator" and version "5.10.0"		update_7		Affected
Mcafee Search vendor "Mcafee"		Epolicy Orchestrator Search vendor "Mcafee" for product "Epolicy Orchestrator"				5.10.0 Search vendor "Mcafee" for product "Epolicy Orchestrator" and version "5.10.0"		update_8		Affected
Mcafee Search vendor "Mcafee"		Epolicy Orchestrator Search vendor "Mcafee" for product "Epolicy Orchestrator"				5.10.0 Search vendor "Mcafee" for product "Epolicy Orchestrator" and version "5.10.0"		update_9		Affected
Oracle Search vendor "Oracle"		Big Data Spatial And Graph Search vendor "Oracle" for product "Big Data Spatial And Graph"				< 23.1 Search vendor "Oracle" for product "Big Data Spatial And Graph" and version " < 23.1"		-		Affected