CVE-2021-45105

Apache Log4j2 versions 2.0-alpha1 through 2.16.0 (excluding 2.12.3) did not protect from uncontrolled recursion from self-referential lookups. This allows an attacker with control over Thread Context Map data to cause a denial of service when a crafted string is interpreted. This issue was fixed in Log4j 2.17.0 and 2.12.3.

Affected packages

Only the org.apache.logging.log4j:log4j-core package is directly affected by this vulnerability. The org.apache.logging.log4j:log4j-api should be kept at the same version as the org.apache.logging.log4j:log4j-core package to ensure compatability if in use.

Log4j is a tool to help the programmer output log statements to a variety of output targets.

Security Fix(es):

Apache Log4j2 versions 2.0-alpha1 through 2.16.0 (excluding 2.12.3) did not protect from uncontrolled recursion from self-referential lookups. This allows an attacker with control over Thread Context Map data to cause a denial of service when a crafted string is interpreted. This issue was fixed in Log4j 2.17.0 and 2.12.3.(CVE-2021-45105) It was found that the fix to address CVE-2021-44228 in Apache Log4j 2.15.0 was incomplete in certain non-default configurations. This could allows attackers with control over Thread Context Map (MDC) input data when the logging configuration uses a non-default Pattern Layout with either a Context Lookup (for example, $${ctx:loginId}) or a Thread Context Map pattern (%X, %mdc, or %MDC) to craft malicious input data using a JNDI Lookup pattern resulting in a denial of service (DOS) attack. Log4j 2.15.0 makes a best-effort attempt to restrict JNDI LDAP lookups to localhost by default. Log4j 2.16.0 fixes this issue by removing support for message lookup patterns and disabling JNDI functionality by default.(CVE-2021-45046) The details of a high-risk vulnerability in Apache Log4j2 have been disclosed. Attackers can use the vulnerability to execute code remotely. Some reports carry suspected POC, Apache Log4j2 is a Java-based logging tool. This tool rewrites the Log4j framework and introduces a large number of rich features. The log framework is widely used in business system development to record log information. In most cases, developers may write error messages caused by user input into the log. The trigger condition of this vulnerability is that as long as the data input by external users will be recorded in the log, it can cause remote code execution.(CVE-2021-44228)

Log4j is a tool to help the programmer output log statements to a variety of output targets.

Security Fix(es):

Apache Log4j2 versions 2.0-alpha1 through 2.16.0 (excluding 2.12.3 and 2.3.1) did not protect from uncontrolled recursion from self-referential lookups. This allows an attacker with control over Thread Context Map data to cause a denial of service when a crafted string is interpreted. This issue was fixed in Log4j 2.17.0, 2.12.3, and 2.3.1.(CVE-2021-45105)

Apache Log4j2 versions 2.0-beta7 through 2.17.0 (excluding security fix releases 2.3.2 and 2.12.4) are vulnerable to a remote code execution (RCE) attack when a configuration uses a JDBC Appender with a JNDI LDAP data source URI when an attacker has control of the target LDAP server. This issue is fixed by limiting JNDI data source names to the java protocol in Log4j2 versions 2.17.1, 2.12.4, and 2.3.2.(CVE-2021-44832)

Log4j is a tool to help the programmer output log statements to a variety of output targets.

Security Fix(es):

It was found that the fix to address CVE-2021-44228 in Apache Log4j 2.15.0 was incomplete in certain non-default configurations. This could allows attackers with control over Thread Context Map (MDC) input data when the logging configuration uses a non-default Pattern Layout with either a Context Lookup (for example, $${ctx:loginId}) or a Thread Context Map pattern (%X, %mdc, or %MDC) to craft malicious input data using a JNDI Lookup pattern resulting in an information leak and remote code execution in some environments and local code execution in all environments. Log4j 2.16.0 (Java 8) and 2.12.2 (Java 7) fix this issue by removing support for message lookup patterns and disabling JNDI functionality by default.(CVE-2021-45046)

Apache Log4j2 versions 2.0-alpha1 through 2.16.0 (excluding 2.12.3 and 2.3.1) did not protect from uncontrolled recursion from self-referential lookups. This allows an attacker with control over Thread Context Map data to cause a denial of service when a crafted string is interpreted. This issue was fixed in Log4j 2.17.0, 2.12.3, and 2.3.1.(CVE-2021-45105)

Apache Log4j2 versions 2.0-beta7 through 2.17.0 (excluding security fix releases 2.3.2 and 2.12.4) are vulnerable to a remote code execution (RCE) attack when a configuration uses a JDBC Appender with a JNDI LDAP data source URI when an attacker has control of the target LDAP server. This issue is fixed by limiting JNDI data source names to the java protocol in Log4j2 versions 2.17.1, 2.12.4, and 2.3.2.(CVE-2021-44832)

Apache Log4j2 versions 2.0-alpha1 through 2.16.0 (excluding 2.12.3 and 2.3.1) did not protect from uncontrolled recursion from self-referential lookups. This allows an attacker with control over Thread Context Map data to cause a denial of service when a crafted string is interpreted. This issue was fixed in Log4j 2.17.0, 2.12.3, and 2.3.1.

Updated log4j packages fix security vulnerability:

Apache Log4j2 versions 2.0-alpha1 through 2.16.0 did not protect from uncontrolled recursion from self-referential lookups. This allows an attacker with control over Thread Context Map data to cause a denial of service when a crafted string is interpreted (CVE-2021-45105).

This update for log4j fixes the following issues:

• Update to 2.17.0
• CVE-2021-45105: Apache Log4j2 does not always protect from infinite recursion in lookup evaluation. (bsc#1193887, bsc#1193888)

This update was imported from the SUSE:SLE-15-SP2:Update update project.

This update for log4j fixes the following issues:

• Update to 2.17.0
• CVE-2021-45105: Apache Log4j2 does not always protect from infinite recursion in lookup evaluation. (bsc#1193887, bsc#1193888)

These are all security issues fixed in the log4j-2.17.0-1.1 package on the GA media of openSUSE Tumbleweed.

Root has patched CVE-2021-45105 in the io.root.org.apache.logging.log4j:log4j-core package for Root:Maven. Multiple fixed versions available.

Hideki Okamoto and Guy Lederfein discovered that Apache Log4j 2 did not protect against infinite recursion in lookup evaluation. A remote attacker could possibly use this issue to cause Apache Log4j 2 to crash, leading to a denial of service. Please see the following link for more information: https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/Log4Shell

It was discovered that Apache Log4j 2 was vulnerable to remote code execution (RCE) attack when configured to use a JDBC Appender with a JNDI LDAP data source URI. A remote attacker could possibly use this issue to cause a crash, leading to a denial of service. (CVE-2021-44832)

Hideki Okamoto and Guy Lederfein discovered that Apache Log4j 2 did not protect against infinite recursion in lookup evaluation. A remote attacker could possibly use this issue to cause Apache Log4j 2 to crash, leading to a denial of service. This issue only affected Ubuntu 18.04 LTS. (CVE-2021-45105)