7.5

CVE-2026-44160: Fluentd: Denial of Service (DoS) via Gzip Decompression Bomb in `in_http` and `in_forward`

Analyzed
AliasesCGA-294q-95f9-4g5jCGA-2rw2-g25j-r5jmCGA-3292-83v9-83qx
Published 08-07-2026Last modified 09-07-2026

Vulnerability summary

CVE-2026-44160 is a high (CVSS 7.5) vulnerability in fluent fluentd. EPSS estimates a 0.62% chance of exploitation in the next 30 days, higher than 49.7% of scored vulnerabilities.

Priority
Prioritisesevere

Severe, CVSS 7.5 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 1% (FIRST, 03-11-2026)

Source freshness unavailable

How is this decided?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.62%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 0 · Related 1
CGA-MX93-43M6-C43V

Timeline

  1. 08-07-2026
    PublishedVulnerability first disclosed.
  2. 09-07-2026
    Last modifiedVulnerability information updated.

Description

Fluentd collects events from various data sources and writes them to files, RDBMS, NoSQL, IaaS, SaaS, Hadoop and so on. Prior to 1.19.3, Fluentd's in_http and in_forward plugins support gzip-compressed data but enforce limits only on compressed payloads through settings such as body_size_limit and chunk_size_limit, allowing crafted compressed payloads to decompress in memory to an excessive size and cause denial of service through memory exhaustion. This issue is fixed in version 1.19.3.

CVSS metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

0.62%

Chance of exploitation in the next 30 days

Percentile

50%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.62% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Chainguard27 products
  • kube-fluentd-operator< 1.18.2-r72
  • ruby3.2-fluentd-1.16All versions (No fix recorded)
  • ruby3.2-fluentd-1.17All versions (No fix recorded)
  • ruby3.2-fluentd-1.18All versions (No fix recorded)
  • ruby3.2-fluentd-kubernetes-daemonset-1.16-kinesisAll versions (No fix recorded)
Wolfi10 products
  • kube-fluentd-operator< 1.18.2-r72
  • ruby3.2-fluentd-kubernetes-daemonset-1.19-kinesis< 1.19.2.1.1-r5
  • ruby3.2-kube-logging-operator-fluentd-outputs< 6.7.0-r7
  • ruby3.3-fluentd-1.17All versions (No fix recorded)
  • ruby3.3-fluentd-kubernetes-daemonset-1.19-kinesis< 1.19.3.1.0-r0
Fluent1 product
Fluentd1 product
RubyGems1 product
  • fluentd< 1.19.3

5 vendors · 40 products

References

7 links