Debian update for tomcat9

Published: 2020-07-18 | Updated: 2024-09-27

Risk	High
Patch available	YES
Number of vulnerabilities	4
CVE-ID	CVE-2020-11996 CVE-2020-13934 CVE-2020-13935 CVE-2020-9484
CWE-ID	CWE-399 CWE-835 CWE-502
Exploitation vector	Network
Public exploit	Public exploit code for vulnerability #1 is available. Public exploit code for vulnerability #2 is available. Public exploit code for vulnerability #3 is available. Public exploit code for vulnerability #4 is available.
Vulnerable software	Debian Linux Operating systems & Components / Operating system tomcat9 (Debian package) Operating systems & Components / Operating system package or component
Vendor	Debian

Security Bulletin

This security bulletin contains information about 4 vulnerabilities.

1) Resource management error

EUVDB-ID: #VU29333

Risk: Medium

CVSSv4.0: 7.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2020-11996

CWE-ID: CWE-399 - Resource Management Errors

Exploit availability: Yes

Description

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

The vulnerability exists due to improper management of internal resources with the application when processing HTTP/2 requests. A remote attacker can send specially crafted sequence of HTTP/2 requests to the affected server and trigger high CPU load for several seconds. A large number of such requests causes denial of service.

Mitigation

Update tomcat9 package to version 9.0.31-1~deb10u2.

Vulnerable software versions

Debian Linux: All versions

tomcat9 (Debian package): before 9.0.31-1~deb10u2

CPE2.3

External links

https://www.debian.org/security/2020/dsa-4727

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. However, proof of concept for this vulnerability is available.

2) Resource management error

EUVDB-ID: #VU29724

Risk: Medium

CVSSv4.0: 7.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2020-13934

CWE-ID: CWE-399 - Resource Management Errors

Exploit availability: No

Description

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

The vulnerability exists due to improper management of internal resources when processing h2 direct connections. A remote attacker can pass specially crafted HTTP/2 requests to the server and consume all available memory.

Mitigation

Update tomcat9 package to version 9.0.31-1~deb10u2.

Vulnerable software versions

Debian Linux: All versions

tomcat9 (Debian package): before 9.0.31-1~deb10u2

CPE2.3

External links

https://www.debian.org/security/2020/dsa-4727

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. However, proof of concept for this vulnerability is available.

3) Infinite loop

EUVDB-ID: #VU29723

Risk: Medium

CVSSv4.0: 7.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2020-13935

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

Exploit availability: Yes

Description

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

The vulnerability exists due to infinite loop when processing payload length in a WebSocket frame. A remote attacker can send a specially crafted request to the application, consume all available system resources and cause denial of service conditions.

Mitigation

Update tomcat9 package to version 9.0.31-1~deb10u2.

Vulnerable software versions

Debian Linux: All versions

tomcat9 (Debian package): before 9.0.31-1~deb10u2

CPE2.3

External links

https://www.debian.org/security/2020/dsa-4727

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. However, proof of concept for this vulnerability is available.

4) Deserialization of Untrusted Data

EUVDB-ID: #VU28158

Risk: High

CVSSv4.0: 8.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Amber]

CVE-ID: CVE-2020-9484

CWE-ID: CWE-502 - Deserialization of Untrusted Data

Exploit availability: Yes

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to insecure input validation when processing serialized data in uploaded files names. A remote attacker can pass specially crafted file name to the application and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system but requires that the server is configured to use PersistenceManager with a FileStore and the attacker knows relative file path from storage location.

Mitigation

Update tomcat9 package to version 9.0.31-1~deb10u2.

Vulnerable software versions

Debian Linux: All versions

tomcat9 (Debian package): before 9.0.31-1~deb10u2

CPE2.3

External links

https://www.debian.org/security/2020/dsa-4727

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. However, proof of concept for this vulnerability is available.