Ubuntu update for apache-log4j2
| Risk | Medium |
| Patch available | YES |
| Number of vulnerabilities | 2 |
| CVE-ID | CVE-2021-44832 CVE-2021-45105 |
| CWE-ID | CWE-94 CWE-835 |
| Exploitation vector | Network |
| Public exploit | Public exploit code for vulnerability #2 is available. |
| Vulnerable software Subscribe |
Ubuntu Operating systems & Components / Operating system liblog4j2-java (Ubuntu package) Operating systems & Components / Operating system package or component |
| Vendor | Canonical Ltd. |
Security Bulletin
This security bulletin contains information about 2 vulnerabilities.
1) Code Injection
EUVDB-ID: #VU59098
Risk: Medium
CVSSv3.1: 5.8 [CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]
CVE-ID: CVE-2021-44832
CWE-ID:
CWE-94 - Improper Control of Generation of Code ('Code Injection')
Exploit availability: No
DescriptionThe vulnerability allows a remote user to execute arbitrary code on the target system.
The vulnerability exists due to improper input validation. A remote user with permission to modify the logging configuration file can construct a malicious configuration using a JDBC Appender with a data source referencing a JNDI URI which can execute remote code.
MitigationUpdate the affected package apache-log4j2 to the latest version.
Vulnerable software versionsUbuntu: 18.04 - 21.10
liblog4j2-java (Ubuntu package): before 2.17.1-0.21.10.1
External linkshttp://ubuntu.com/security/notices/USN-5222-1
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote authenticated privileged user via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
2) Infinite loop
EUVDB-ID: #VU59051
Risk: Medium
CVSSv3.1: 6.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C]
CVE-ID: CVE-2021-45105
CWE-ID:
CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to infinite loop within the StrSubstitutor class. A remote attacker can pass specially crafted input to the application, consume all available system resources and cause denial of service conditions.
Payload example: ${${::-${::-$${::-j}}}}
MitigationUpdate the affected package apache-log4j2 to the latest version.
Vulnerable software versionsUbuntu: 18.04 - 21.10
liblog4j2-java (Ubuntu package): before 2.17.1-0.21.10.1
External linkshttp://ubuntu.com/security/notices/USN-5222-1
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.
