What is CVE-2026-44160?
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.
The record classifies CVE-2026-44160 under weakness class CWE-409. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 107 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 7.5 — HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS (FIRST)
- 0.6% probability of exploitation in the next 30 days, higher than 48.1% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 5.7/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2026-07-08, last modified 2026-07-09
Is CVE-2026-44160 being exploited?
It currently carries a trending score of 24 in the Threadlinqs vulnerability feed.
Affected products and versions
- fluent: fluentd
Affected software packages:
rubygems:fluentd— patched in 1.19.3
How to fix CVE-2026-44160
The record marks a vendor fix as available for CVE-2026-44160. Fixed versions are recorded for 1 package: rubygems:fluentd 1.19.3. Patch reference: https://github.com/fluent/fluentd/commit/f5f2b7cddf8aab3932e6dec9fa367a5f3eb27e10. Vendor advisory: https://github.com/fluent/fluentd/security/advisories/GHSA-j9cw-hwqf-85w7. Apply the vendor fix referenced above to every affected product listed in this record, then confirm the running version against the vendor advisory.
Threat activity tracking CVE-2026-44160
1 tracked threat in the Threadlinqs corpus references CVE-2026-44160, either in the campaign’s CVE list or as an indicator on the campaign record.
Sources
Enriched from CVE.org, NVD, FIRST EPSS, GitHub Security Advisories. Last verified by Threadlinqs on . This product uses the NVD API but is not endorsed or certified by the NVD.