CVE-2026-34478
Description
A flaw was found in Apache Log4j Core. This vulnerability allows for log injection through the use of Carriage Return Line Feed (CRLF) sequences. This occurs because security-related configuration attributes were silently renamed, impacting users who directly configure Rfc5424Layout with stream-based syslog services. An attacker could exploit this to inject malicious data into log files, potentially obscuring critical security events or manipulating system records.
Statement
This vulnerability allows log injection via CRLF sequences due to silently renamed security attributes in Rfc5424Layout. This affects Red Hat products that directly configure Rfc5424Layout with stream-based syslog services, potentially enabling an attacker to obscure or manipulate log records. This impact is limited to specific configurations, as users of the SyslogAppender are not affected.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.8 | 7.5 | N/A |
| Attack Vector | Network | Network | N/A |
| Attack Complexity | Low | Low | N/A |
| Privileges Required | None | None | N/A |
| User Interaction | None | None | N/A |
| Scope | Changed | Unchanged | N/A |
| Confidentiality | None | None | N/A |
| Integrity Impact | Low | High | N/A |
| Availability Impact | None | None | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
NVD: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Application Data
Frequently Asked Questions
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