CVE-2026-44160

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

HIGH
7.5
CVSS Score
Published: July 8, 2026 at 09:24 PM UTC
Updated: October 25, 2026 at 05:10 PM UTC
2 products affected across 2 vendorsFluentdFluentd

Using fluentd by fluent?

Get instant alerts when new vulnerabilities affect fluentd - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH7.5
Exploit prediction
EPSS 0.6%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1.19.3
Affected range stops below 1.19.3, so it looks safe — our inference, not a vendor statement
v < 1.19.3
Affected range stops below 1.19.3, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (4)

x_refsource_CONFIRMMitigationVendor Advisory
Source: cverecord
https://github.com/fluent/fluentd/security/advisories/GHSA-j9cw-hwqf-85w7
x_refsource_MISCIssue TrackingPatch
Source: cverecord
https://github.com/fluent/fluentd/pull/5393
x_refsource_MISCProductRelease Notes
Source: cverecord
https://github.com/fluent/fluentd/releases/tag/v1.19.3

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-409

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card