CVE-2025-54812
Improper Output Neutralization for Logs vulnerability in Apache Log4cxx.
Does this matter?
Lower severity and a low EPSS score (1.19%). Track it; it rarely justifies an emergency change on its own.
Description
Improper Output Neutralization for Logs vulnerability in Apache Log4cxx. When using HTMLLayout, logger names are not properly escaped when writing out to the HTML file. If untrusted data is used to retrieve the name of a logger, an attacker could theoretically inject HTML or Javascript in order to hide information from logs or steal data from the user. In order to activate this, the following sequence must occur: * Log4cxx is configured to use HTMLLayout. * Logger name comes from an untrusted string * Logger with compromised name logs a message * User opens the generated HTML log file in their browser, leading to potential XSS Because logger names are generally constant strings, we assess the impact to users as LOW This issue affects Apache Log4cxx: before 1.5.0. Users are recommended to upgrade to version 1.5.0, which fixes the issue.
- CVSS 4.0
- 2.1 LOWCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 1.19% probability · 66th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-117
- Affected
- apache/log4cxx
- Source
- security@apache.org
References
- https://github.com/apache/logging-log4cxx/pull/509Issue Tracking, Patch
- https://github.com/apache/logging-log4cxx/pull/514Issue Tracking, Patch
- https://logging.apache.org/security.html#CVE-2025-54812Vendor Advisory
- http://www.openwall.com/lists/oss-security/2025/08/22/2
- https://lists.debian.org/debian-lts-announce/2025/10/msg00002.html
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.