Authentication Bypass Affecting logstash-9.4 package, versions <9.4.4-r0


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.27% (19th percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-LOGSTASH94-18216891
  • published23 Jul 2026
  • disclosed14 Jul 2026

Introduced: 14 Jul 2026

CVE-2026-47737  (opens in a new tab)
CWE-290  (opens in a new tab)
CWE-345  (opens in a new tab)

How to fix?

Upgrade Chainguard logstash-9.4 to version 9.4.4-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream logstash-9.4 package and not the logstash-9.4 package as distributed by Chainguard. See How to fix? for Chainguard relevant fixed versions and status.

Puma is a Ruby/Rack web server built for parallelism. From 5.5.0 until 7.2.1 and 8.0.2, Puma is vulnerable to source IP spoofing when set_remote_address proxy_protocol: :v1 is enabled and persistent connections are used because Puma incorrectly re-parses PROXY protocol headers after each keep-alive request on the same connection, allowing an attacker to inject a second PROXY header and overwrite REMOTE_ADDR. This issue is fixed in versions 7.2.1 and 8.0.2.

CVSS Base Scores

version 3.1