How severe is CVE-2025-54812?

CVE-2025-54812 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2025-54812 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-54812?

CVE-2025-54812 affects Apache Log4cxx. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-54812?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-54812 have an EU (EUVD) identifier?

Yes. CVE-2025-54812 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-25621.

When was CVE-2025-54812 published?

CVE-2025-54812 was published on 2025-08-22 and last updated on 2026-06-17.

CVE-2025-54812

CVE-2025-54812 is a medium-severity vulnerability in Apache Log4cxx with a CVSS 3.x base score of 5.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-117.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
CVSS v4: 2.1
EPSS exploit prediction: 1% (61st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-25621
Weakness: CWE-117
Affected product: Apache Log4cxx
Published: 2025-08-22
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-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 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.
How severe is CVE-2025-54812?: CVE-2025-54812 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2025-54812 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-54812?: CVE-2025-54812 affects Apache Log4cxx. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-54812?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-54812 have an EU (EUVD) identifier?: Yes. CVE-2025-54812 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-25621.
When was CVE-2025-54812 published?: CVE-2025-54812 was published on 2025-08-22 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:apache:log4cxx:*:*:*:*:*:*:*:*

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