CVE-2023-26464 Apache Log4j 1.x (EOL) allows DoS in Chainsaw and SocketAppender
Attackers can cause Denial of Service in Log4j 1.x by triggering memory exhaustion via specially crafted objects in Chainsaw or SocketAppender components.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-26464?
CVE-2023-26464 is a high-severity denial of service vulnerability in Apache Log4j, published on 10 Mar 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
** UNSUPPORTED WHEN ASSIGNED **
When using the Chainsaw or SocketAppender components with Log4j 1.x on JRE less than 1.7, an attacker that manages to cause a logging entry involving a specially-crafted (ie, deeply nested) hashmap or hashtable (depending on which logging component is in use) to be processed could exhaust the available memory in the virtual machine and achieve Denial of Service when the object is deserialized.
This issue affects Apache Log4j before 2. Affected users are recommended to update to Log4j 2.x.
NOTE: This vulnerability only affects products that are no longer supported by the maintainer.
Weakness: CWE-502
Which versions are affected by CVE-2023-26464?
4 open source packages ship an affected version, including org.apache.logging.log4j:log4j-core and log4j:log4j. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
org.apache.logging.log4j:log4j-core Maven | From 1.0.4 | 2.0 |
org.apache.logging.log4j:log4j-core Maven | From 1.0.4 | 2.0 |
log4j:log4j Maven | From 1.0.4 | 2.0 |
log4j:log4j Maven | From 1.0.4 | 2.0 |
Products include Apache Log4j.
How do I fix CVE-2023-26464?
Upgrade org.apache.logging.log4j:log4j-core to 2.0 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2023-26464 being exploited?
There is no known exploitation of CVE-2023-26464 in the wild and no public exploit code.
Other vulnerabilities in Apache Log4j
- CVE-2021-44228 Apache Log4j2 Remote Code Execution
- CVE-2021-45046 Apache Log4j2 Deserialization of Untrusted Data
- CVE-2022-23305 SQL injection in JDBC Appender in Apache Log4j V1
- CVE-2017-5645 Deserialization of Untrusted Data in Log4j
- CVE-2022-23302 Deserialization of untrusted data in JMSSink in Apache Log4j 1.x
Sources
Also known as CLSA-2025-1754352206, GHSA-vp98-w2p3-mv35, MINI-mf8p-gm85-4wjc, MINI-w8mq-62jw-ggrv, ROOT-APP-MAVEN-CVE-2023-26464, UBUNTU-CVE-2023-26464.