fluent-plugin-opentelemetry is a Fluentd input and output plugin for forwarding OpenTelemetry Protocol data. Prior to 0.5.3, the in_opentelemetry HTTP input read the entire incoming request body and decompressed payloads into memory without enforcing maximum size thresholds. When an OpenTelemetry ingestion endpoint was exposed to an untrusted network, an attacker could send an excessively large request or a highly compressed payload that expanded in memory. The resulting memory exhaustion could cause the operating system to terminate the Fluentd process, disrupting all log collection and forwarding on the affected node. This issue is fixed in version 0.5.3.
CVE-2026-44163
MEDIUMPre-NVD 5.35.3—
EchelonGraph scoreMEDIUM confidence
This medium-severity CVE scores 5.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 73% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
Triggered by: NVD CVSS baseline
Sources: epss, secondary
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.3Exploit: None knownExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 5.3
- EG Score
- 5.3(medium)
- EG Risk
- 39(Track)EG Risk 39/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity53% × 45%Exploitation0% × 40%Automatability100% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 27%
- KEV
- Not listed
Published
June 26, 2026
Last Modified
September 16, 2026
Advisory Details (2)
Auto-updated Sep 15, 2026Patch available. Sources: github, github_commit.
github_commit
commit ce6c1f2a7741 (fluent-plugins-nursery/fluent-plugin-opentelemetry)
Fix landed in fluent-plugins-nursery/fluent-plugin-opentelemetry commit ce6c1f2a7741 — awaiting tagged release
https://github.com/fluent-plugins-nursery/fluent-plugin-opentelemetry/commit/ce6c1f2a7741592c8a79afbe75fded9e8ebfa92dgithub Patch Available
Denial of Service (DoS) via Large Payloads and Decompression Bombs in `in_opentelemetry` · Advisory · fluent-plugins-nursery/fluent-plugin-opentelemetry · GitHub
https://github.com/fluent-plugins-nursery/fluent-plugin-opentelemetry/security/advisories/GHSA-2jc5-xhx8-qj6hVendor Advisories for CVE-2026-44163(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Affected Packages
(1 across 1 ecosystem)
RubyGems(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| fluent-plugin-opentelemetry | 0.1.0 ... 0.5.2 (7 versions) | 0.5.3 | — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 7× in last 7d / 7× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-09-18 19:28 UTCEPSS rescore
- 2026-09-18 07:13 UTCEG score recompute
- 2026-09-17 19:31 UTCEPSS rescore
- 2026-09-16 17:53 UTCEG score recompute
- 2026-09-16 17:11 UTCEG score recompute
- 2026-09-16 14:08 UTCEPSS rescore
- 2026-09-15 16:35 UTCEG score recompute
- 2026-07-31 01:24 UTCEG score recompute
- 2026-07-26 14:34 UTCEG score recompute
- 2026-07-23 03:14 UTCEG score recompute
- 2026-06-26 17:37 UTCEG score recompute
Frequently asked(5)
What is CVE-2026-44163?
CVE-2026-44163 is a medium vulnerability published on June 26, 2026. fluent-plugin-opentelemetry is a Fluentd input and output plugin for forwarding OpenTelemetry Protocol data. Prior to 0.5.3, the in_opentelemetry HTTP input read the entire incoming request body and decompressed payloads into memory without enforcing maximum size thresholds. When an OpenTelemetry…
When was CVE-2026-44163 disclosed?
CVE-2026-44163 was first published in the National Vulnerability Database on June 26, 2026, with the most recent update on September 16, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-44163 actively exploited?
CVE-2026-44163 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 72.9% of all scored CVEs.
What is the CVSS score of CVE-2026-44163?
CVE-2026-44163 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-44163?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-44163, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-44163
Is Your Infrastructure Affected by CVE-2026-44163?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.