9.8

CVE-2022-39379: Fluentd vulnerable to remote code execution due to insecure deserialization (in non-default configuration)

Modified
AliasesGHSA-fppq-mj76-fpj2BIT-fluentd-2022-39379
Published 02-11-2022Last modified 23-04-2025

Vulnerability summary

CVE-2022-39379 is a critical (CVSS 9.8) Deserialization of Untrusted Data vulnerability in fedoraproject fedora. EPSS estimates a 44.98% chance of exploitation in the next 30 days, higher than 98.7% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 3.1, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
9.8/10
010
Critical · v3.1 (NVD)
EPSS score
44.98%
0%100%
High · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 02-11-2022
    PublishedVulnerability first disclosed.
  2. 23-04-2025
    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. 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`.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

44.98%

Chance of exploitation in the next 30 days

Percentile

99%

Versus all other CVEs

30-day change

No change 0.00 pp

From 44.98% 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, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Fedoraproject1 product
Fluent1 product
Fluentd1 product
RubyGems1 product
  • fluentd≥ 1.13.2, < 1.15.3

4 vendors · 4 products

References

7 links