CVE-2026-34481 (GCVE-0-2026-34481)
Vulnerability from cvelistv5
Published
2026-04-10 15:43
Modified
2026-04-10 17:41
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-116 - Improper Encoding or Escaping of Output
Summary
Apache Log4j's JsonTemplateLayout https://logging.apache.org/log4j/2.x/manual/json-template-layout.html , in versions up to and including 2.25.3, produces invalid JSON output when log events contain non-finite floating-point values (NaN, Infinity, or -Infinity), which are prohibited by RFC 8259. This may cause downstream log processing systems to reject or fail to index affected records.
An attacker can exploit this issue only if both of the following conditions are met:
* The application uses JsonTemplateLayout.
* The application logs a MapMessage containing an attacker-controlled floating-point value.
Users are advised to upgrade to Apache Log4j JSON Template Layout 2.25.4, which corrects this issue.
References
| URL | Tags | |
|---|---|---|
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Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Apache Software Foundation | Apache Log4j JSON Template Layout |
Version: 2.14.0 Version: 3.0.0-alpha1 cpe:2.3:a:apache:log4j_layout_template_json:*:*:*:*:*:*:*:* |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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