==========================================================================
Ubuntu Security Notice USN-6049-1
April 28, 2023

netty vulnerabilities
==========================================================================

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 22.10
- Ubuntu 22.04 LTS
- Ubuntu 20.04 ESM
- Ubuntu 18.04 ESM
- Ubuntu 16.04 ESM

Summary:

Several security issues were fixed in Netty.

Software Description:
- netty: Java NIO client/server socket framework

Details:

It was discovered that Netty's Zlib decoders did not limit memory
allocations. A remote attacker could possibly use this issue to cause
Netty to exhaust memory via malicious input, leading to a denial of
service. This issue only affected Ubuntu 16.04 ESM and Ubuntu 20.04 ESM.
(CVE-2020-11612)

It was discovered that Netty created temporary files with excessive
permissions. A local attacker could possibly use this issue to expose
sensitive information. This issue only affected Ubuntu 16.04 ESM, Ubuntu
18.04 ESM, and Ubuntu 20.04 ESM. (CVE-2021-21290)

It was discovered that Netty did not properly validate content-length
headers. A remote attacker could possibly use this issue to smuggle
requests. This issue was only fixed in Ubuntu 20.04 ESM. (CVE-2021-21295,
CVE-2021-21409)

It was discovered that Netty's Bzip2 decompression decoder did not limit
the decompressed output data size. A remote attacker could possibly use
this issue to cause Netty to exhaust memory via malicious input, leading
to a denial of service. This issue only affected Ubuntu 18.04 ESM, Ubuntu
20.04 ESM, Ubuntu 22.04 LTS, and Ubuntu 22.10. (CVE-2021-37136)

It was discovered that Netty's Snappy frame decoder function did not limit
chunk lengths. A remote attacker could possibly use this issue to cause
Netty to exhaust memory via malicious input, leading to a denial of
service. (CVE-2021-37137)

It was discovered that Netty did not properly handle control chars at the
beginning and end of header names. A remote attacker could possibly use
this issue to smuggle requests. This issue only affected Ubuntu 18.04 ESM,
Ubuntu 20.04 ESM, Ubuntu 22.04 LTS, and Ubuntu 22.10. (CVE-2021-43797)

It was discovered that Netty could be made into an infinite recursion when
parsing a malformed crafted message. A remote attacker could possibly use
this issue to cause Netty to crash, leading to a denial of service. This
issue only affected Ubuntu 20.04 ESM, Ubuntu 22.04 LTS, and Ubuntu 22.10.
(CVE-2022-41881)

It was discovered that Netty did not validate header values under certain
circumstances. A remote attacker could possibly use this issue to perform
HTTP response splitting via malicious header values. This issue only
affected Ubuntu 18.04 ESM, Ubuntu 20.04 ESM, Ubuntu 22.04 LTS, and Ubuntu
22.10. (CVE-2022-41915)

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 22.10:
   libnetty-java                   1:4.1.48-5ubuntu0.1

Ubuntu 22.04 LTS:
   libnetty-java                   1:4.1.48-4+deb11u1build0.22.04.1

Ubuntu 20.04 ESM:
   libnetty-java                   1:4.1.45-1ubuntu0.1~esm1

Ubuntu 18.04 ESM:
   libnetty-java                   1:4.1.7-4ubuntu0.1+esm2

Ubuntu 16.04 ESM:
   libnetty-java                   1:4.0.34-1ubuntu0.1~esm1

In general, a standard system update will make all the necessary changes.

References:
   https://ubuntu.com/security/notices/USN-6049-1
   CVE-2020-11612, CVE-2021-21290, CVE-2021-21295, CVE-2021-21409,
   CVE-2021-37136, CVE-2021-37137, CVE-2021-43797, CVE-2022-41881,
   CVE-2022-41915

Package Information:
   https://launchpad.net/ubuntu/+source/netty/1:4.1.48-5ubuntu0.1
https://launchpad.net/ubuntu/+source/netty/1:4.1.48-4+deb11u1build0.22.04.1