# CVE-2022-39379 — fluent fluentd

> As of 2025-04-23, CVE-2022-39379 is a LOW-severity vulnerability in fluent fluentd, CVSS v3.1 3.1, EPSS 44.9% (98.7th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2022-39379, most recently “Multiple Fluentd Vulnerabilities: RCE via Tag Placeholder (CVE-2026-44024), Info Disclosure (CVE-2026-44025), Decompression Bomb DoS (CVE-2026-44160), and SSRF (CVE-2026-44161)”.

**Last updated:** 2025-04-23

## What is CVE-2022-39379?

Fluentd collects events from various data sources and writes them to files, RDBMS, NoSQL, IaaS, SaaS, Hadoop and so on. A remote code execution (RCE) vulnerability in non-default configurations of Fluentd allows unauthenticated attackers to execute arbitrary code via specially crafted JSON payloads. Fluentd setups are only affected if the environment variable `FLUENT_OJ_OPTION_MODE` is explicitly set to `object`. Please note: The option FLUENT_OJ_OPTION_MODE was introduced in Fluentd version 1.13.2. Earlier versions of Fluentd are not affected by this vulnerability. This issue was patched in version 1.15.3. As a workaround do not use `FLUENT_OJ_OPTION_MODE=object`.

The record classifies CVE-2022-39379 under weakness class [CWE-502](https://intel.threadlinqs.com/cwe/CWE-502). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs low-privilege credentials, needs no user interaction. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 1451 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 3.1 — LOW (`CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N`)
- **EPSS (FIRST):** 44.9% probability of exploitation in the next 30 days, higher than 98.7% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 5.5/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2022-11-02, last modified 2025-04-23

## Is CVE-2022-39379 being exploited?

It currently carries a trending score of 30 in the Threadlinqs vulnerability feed.

## Affected products and versions

- [fluent](https://intel.threadlinqs.com/vendors/fluent): fluentd

## How to fix CVE-2022-39379

No vendor patch reference has been recorded for CVE-2022-39379 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2022-39379

1 tracked threat in the Threadlinqs corpus references CVE-2022-39379, either in the campaign’s CVE list or as an indicator on the campaign record.

- [Multiple Fluentd Vulnerabilities: RCE via Tag Placeholder (CVE-2026-44024), Info Disclosure (CVE-2026-44025), Decompression Bomb DoS (CVE-2026-44160), and SSRF (CVE-2026-44161)](https://intel.threadlinqs.com/threat/TL-2026-1041) — HIGH · 2026-07-01

## Sources

Enriched from CVE.org, FIRST EPSS. Last verified by Threadlinqs on 2026-10-10.

**Vendor advisory and patch**

- [lists.fedoraproject.org — vendor advisory](https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MYD5QV66OLDHES6IKVYYM3Y3YID3VVCO/)

**Other references**

- [github.com](https://github.com/fluent/fluentd/security/advisories/GHSA-fppq-mj76-fpj2)
- [github.com (48e5b85dab1b6d4c273090d538fc11b3f2fd8135)](https://github.com/fluent/fluentd/commit/48e5b85dab1b6d4c273090d538fc11b3f2fd8135)

Canonical: https://intel.threadlinqs.com/cve/CVE-2022-39379
Full detection coverage and IOCs for threats exploiting CVE-2022-39379 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp