Debian update for netty

Published: 2021-04-06 | Updated: 2025-02-11

Risk	Medium
Patch available	YES
Number of vulnerabilities	7
CVE-ID	CVE-2019-20444 CVE-2019-20445 CVE-2020-7238 CVE-2020-11612 CVE-2021-21290 CVE-2021-21295 CVE-2021-21409
CWE-ID	CWE-444 CWE-113 CWE-400 CWE-312
Exploitation vector	Network
Public exploit	Public exploit code for vulnerability #1 is available.
Vulnerable software	netty (Debian package) Operating systems & Components / Operating system package or component
Vendor	Debian

Security Bulletin

This security bulletin contains information about 7 vulnerabilities.

1) Inconsistent interpretation of HTTP requests

EUVDB-ID: #VU25355

Risk: Medium

CVSSv4.0: 5.5 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2019-20444

CWE-ID: CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling')

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform HTTP request smuggling attacks.

The vulnerability exists due to incorrect processing of HTTP headers without the colon within the HttpObjectDecoder.java file in Netty. A remote attacker can send a specially crafted HTTP request to the application and perform HTTP request smuggling attack.

Mitigation

Update netty package to version 1:4.1.33-1+deb10u2.

Vulnerable software versions

netty (Debian package): 1:4.1.7-1 - 4.1.33-1+deb10u1

CPE2.3

External links

https://www.debian.org/security/2021/dsa-4885

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) HTTP response splitting

EUVDB-ID: #VU25598

Risk: Medium

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2019-20445

CWE-ID: CWE-113 - Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Response Splitting')

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform HTTP splitting attacks.

The vulnerability exists due to software does not corrector process CRLF character sequences within the HttpObjectDecoder.java in Netty, which allows a Content-Length header to be accompanied by a second Content-Length header, or by a Transfer-Encoding header. A remote attacker can send specially crafted request containing CRLF sequence and make the application to send a split HTTP response.

Successful exploitation of the vulnerability may allow an attacker perform cache poisoning attack.

Mitigation

Update netty package to version 1:4.1.33-1+deb10u2.

Vulnerable software versions

netty (Debian package): 1:4.1.7-1 - 4.1.33-1+deb10u1

CPE2.3

External links

https://www.debian.org/security/2021/dsa-4885

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.

3) Inconsistent interpretation of HTTP requests

EUVDB-ID: #VU25353

Risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-7238

CWE-ID: CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling')

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform HTTP request smuggling attack.

The vulnerability exists due to improper input validation when processing a whitespace before the colon in HTTP headers (e.g. "Transfer-Encoding : chunked") and a later Content-Length header. A remote attacker can send a specially crafted HTTP request and perform HTTP request smuggling attack.

This issue exists because of an incomplete fix for CVE-2019-16869 (SB2019092616).

Mitigation

Update netty package to version 1:4.1.33-1+deb10u2.

Vulnerable software versions

netty (Debian package): 1:4.1.7-1 - 4.1.33-1+deb10u1

CPE2.3

External links

https://www.debian.org/security/2021/dsa-4885

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.

4) Resource exhaustion

EUVDB-ID: #VU27513

Risk: Medium

CVSSv4.0: 6.6 [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:U/U:Green]

CVE-ID: CVE-2020-11612

CWE-ID: CWE-400 - Resource exhaustion

Exploit availability: No

Description

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

The vulnerability exists due to application does not properly control consumption of internal resources within ZlibDecoders in Netty while decoding a ZlibEncoded byte stream. A remote attacker can trigger resource exhaustion by passing an overly large ZlibEncoded byte stream to the Netty server, forcing the server to allocate all of its free memory to a single decoder.

Mitigation

Update netty package to version 1:4.1.33-1+deb10u2.

Vulnerable software versions

netty (Debian package): 1:4.1.7-1 - 4.1.33-1+deb10u1

CPE2.3

External links

https://www.debian.org/security/2021/dsa-4885

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.

5) Cleartext storage of sensitive information

EUVDB-ID: #VU51835

Risk: Low

CVSSv4.0: 1.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-21290

CWE-ID: CWE-312 - Cleartext Storage of Sensitive Information

Exploit availability: No

Description

The vulnerability allows a local user to gain access to sensitive information.

The vulnerability exists due to insecure usage of temporary files in AbstractDiskHttpData method in Netty. The application stores sensitive information in temporary file that has insecure permissions. A local user can view application's temporary file and gain access to potentially sensitive data.

Mitigation

Update netty package to version 1:4.1.33-1+deb10u2.

Vulnerable software versions

netty (Debian package): 1:4.1.7-1 - 4.1.33-1+deb10u1

CPE2.3

External links

https://www.debian.org/security/2021/dsa-4885

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

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

6) Inconsistent interpretation of HTTP requests

EUVDB-ID: #VU51836

Risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-21295

CWE-ID: CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling')

Exploit availability: No

Description

The vulnerability allows a remote attacker to preform HTTP request smuggling attacks.

The vulnerability exists due to improper validation of HTTP requests in io.netty:netty-codec-http2 when converting HTTP/2 to HTTP/1 streams. A remote attacker can send a specially crafted HTTP request to the server and smuggle arbitrary HTTP headers.

Successful exploitation of vulnerability may allow an attacker to poison HTTP cache and perform phishing attacks.

Mitigation

Update netty package to version 1:4.1.33-1+deb10u2.

Vulnerable software versions

netty (Debian package): 1:4.1.7-1 - 4.1.33-1+deb10u1

CPE2.3

External links

https://www.debian.org/security/2021/dsa-4885

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.

7) Inconsistent interpretation of HTTP requests

EUVDB-ID: #VU51837

Risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-21409

CWE-ID: CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling')

Exploit availability: No

Description

The vulnerability allows a remote attacker to preform HTTP request smuggling attacks.

The vulnerability exists due to improper validation of HTTP requests in io.netty:netty-codec-http2 in Netty, if the request only uses a single Http2HeaderFrame with the endStream set to to true. A remote attacker can send a specially crafted HTTP request to the server and smuggle arbitrary HTTP headers.

Successful exploitation of vulnerability may allow an attacker to poison HTTP cache and perform phishing attacks.

Mitigation

Update netty package to version 1:4.1.33-1+deb10u2.

Vulnerable software versions

netty (Debian package): 1:4.1.7-1 - 4.1.33-1+deb10u1

CPE2.3

External links

https://www.debian.org/security/2021/dsa-4885

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.