Information disclosure in Apache Tomcat

Published: 2020-12-04

Risk	Medium
Patch available	YES
Number of vulnerabilities	1
CVE-ID	CVE-2020-17527
CWE-ID	CWE-399
Exploitation vector	Network
Public exploit	N/A
Vulnerable software Subscribe	Apache Tomcat Server applications / Web servers
Vendor	Apache Foundation

Security Bulletin

This security bulletin contains one medium risk vulnerability.

1) Resource management error

EUVDB-ID: #VU48779

Risk: Medium

CVSSv3.1: 4.6 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-17527

CWE-ID: CWE-399 - Resource Management Errors

Exploit availability: No

Description

The vulnerability allows a remote attacker to gain access to sensitive information.

The vulnerability exists due to improper management of internal resources within the application when processing HTTP/2 requests in Apache Tomcat. The web server can re-use an HTTP request header value from the previous stream received on an HTTP/2 connection for the request associated with the subsequent stream. As a result a remote attacker can obtain sensitive information from another HTTP request.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Apache Tomcat: 8.0.0 - 10.0.0.0-M1

External links

http://lists.apache.org/thread.html/r8a227ac6a755a6406c1cc47dd48800e973d4cf13fe7fe68ac59c679c@%3Cdev.tomcat.apache.org%3E
http://lists.apache.org/thread.html/raa0e9ad388c1e6fd1e301b5e080f9439f64cb4178119a86a4801cc53@%3Cdev.tomcat.apache.org%3E
http://lists.apache.org/thread.html/rce5ac9a40173651d540babce59f6f3825f12c6d4e886ba00823b11e5%40%3Cannounce.tomcat.apache.org%3E
http://lists.apache.org/thread.html/rce5ac9a40173651d540babce59f6f3825f12c6d4e886ba00823b11e5@%3Cannounce.apache.org%3E
http://lists.apache.org/thread.html/rce5ac9a40173651d540babce59f6f3825f12c6d4e886ba00823b11e5@%3Cannounce.tomcat.apache.org%3E
http://lists.apache.org/thread.html/rd5babd13d7a350b369b2f647b4dd32ce678af42f9aba5389df1ae6ca@%3Cusers.tomcat.apache.org%3E

Q & A

Can this vulnerability be exploited remotely?

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

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

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