Improper Encoding or Escaping of Output Affecting apache-pulsar-4.0 package, versions <4.0.9-r11


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

EPSS
0.17% (38th percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-APACHEPULSAR40-16118364
  • published21 Apr 2026
  • disclosed10 Apr 2026

Introduced: 10 Apr 2026

CVE-2026-34481  (opens in a new tab)
CWE-116  (opens in a new tab)

How to fix?

Upgrade Chainguard apache-pulsar-4.0 to version 4.0.9-r11 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream apache-pulsar-4.0 package and not the apache-pulsar-4.0 package as distributed by Chainguard. See How to fix? for Chainguard relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1