1) Infinite loop

EUVDB-ID: #VU56634

Risk: Medium

CVSSv3.1: 5.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-41079

CWE-ID: CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to infinite loop when processing certain TLS packets. A remote attacker can send a specially crafted packet to the application, consume all available system resources and cause denial of service conditions.

Successful exploitation of vulnerability requires that Apache Tomcat is configured to use NIO+OpenSSL or NIO2+OpenSSL for TLS.

Mitigation

Update the affected packages:

noarch:
    tomcat8-el-3.0-api-8.5.69-1.88.amzn1.noarch
    tomcat8-docs-webapp-8.5.69-1.88.amzn1.noarch
    tomcat8-jsp-2.3-api-8.5.69-1.88.amzn1.noarch
    tomcat8-javadoc-8.5.69-1.88.amzn1.noarch
    tomcat8-lib-8.5.69-1.88.amzn1.noarch
    tomcat8-servlet-3.1-api-8.5.69-1.88.amzn1.noarch
    tomcat8-8.5.69-1.88.amzn1.noarch
    tomcat8-admin-webapps-8.5.69-1.88.amzn1.noarch
    tomcat8-log4j-8.5.69-1.88.amzn1.noarch
    tomcat8-webapps-8.5.69-1.88.amzn1.noarch

src:
    tomcat8-8.5.69-1.88.amzn1.src

Vulnerable software versions

Amazon Linux AMI: 2017.03

CPE2.3

• cpe:2.3:o:amazon_web_services:amazon_linux_ami:2017.03:*:*:*:*:*:*:*
• Full software list in CPE2.3 format available after registration.

External links

http://alas.aws.amazon.com/ALAS-2021-1547.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.