CVE-2025-54812
published 2025-08-22CVE-2025-54812: Improper Output Neutralization for Logs vulnerability in Apache Log4cxx. When using HTMLLayout, logger names are not properly escaped when writing out to the…
PriorityP428medium5.4CVSS 3.1
AVNACLPRLUIRSCCLILAN
EPSS
1.08%
61.3th percentile
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.
Affected
8 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| apache | log4cxx | < 1.5.0 | 1.5.0 |
| apache | log4cxx | >= 0 < 0.11.0-2+deb11u1 | 0.11.0-2+deb11u1 |
| apache | log4cxx | >= 0 < 1.0.0-1+deb12u1 | 1.0.0-1+deb12u1 |
| apache | log4cxx | >= 0 < 1.4.0-1+deb13u1 | 1.4.0-1+deb13u1 |
| apache | log4cxx | >= 0 < 1.4.0-1.1 | 1.4.0-1.1 |
| apache | logging | — | — |
| apache_software_foundation | apache_log4cxx | < 1.5.0 | 1.5.0 |
| debian | log4cxx | < log4cxx 1.0.0-1+deb12u1 (bookworm) | log4cxx 1.0.0-1+deb12u1 (bookworm) |
CVSS provenance
nvdv3.15.4MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
nvdv4.02.1LOWCVSS: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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
osv2.1LOW
vendor_apache2.1LOW
vendor_debian2.1LOW
vendor_redhat2.1LOW
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Red Hat
log4cxx: Log4cxx HTMLLayout XSS Vulnerability
vendor_redhat·2025-08-22·CVSS 2.1
CVE-2025-54812 [LOW] CWE-117 log4cxx: Log4cxx HTMLLayout XSS Vulnerability
log4cxx: Log4cxx HTMLLayout XSS Vulnerability
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 Lo
Debian
CVE-2025-54812: log4cxx - Improper Output Neutralization for Logs vulnerability in Apache Log4cxx. When ...
vendor_debian·2025·CVSS 2.1
CVE-2025-54812 [LOW] CVE-2025-54812: log4cxx - Improper Output Neutralization for Logs vulnerability in Apache Log4cxx. When ...
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 u
Apache
Apache logging: CVE-2025-54812
vendor_apache·CVSS 2.1
CVE-2025-54812 [LOW] Apache logging: CVE-2025-54812
Apache logging: CVE-2025-54812
Summary Improper HTML escaping in HTMLLayout CVSS 4.x Score & Vector 2.1 LOW (CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N) Components affected Log4cxx Versions affected [0, 1.5.0) Versions fixed 1.5.0
Severity: low
Affected versions: 1.5.0
OSV
CVE-2025-54812: Improper Output Neutralization for Logs vulnerability in Apache Log4cxx
osv·2025-08-22·CVSS 2.1
CVE-2025-54812 [LOW] CVE-2025-54812: Improper Output Neutralization for Logs vulnerability in Apache Log4cxx
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 u
GHSA
GHSA-7mpr-gcjx-jcmw: Improper Output Neutralization for Logs vulnerability in Apache Log4cxx
ghsa_unreviewed·2025-08-22
CVE-2025-54812 [LOW] CWE-117 GHSA-7mpr-gcjx-jcmw: Improper Output Neutralization for Logs vulnerability in Apache Log4cxx
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 rec
No detection rules found.
No public exploits indexed.
2025-08-22
Published