How severe is GHSA-fppq-mj76-fpj2?

GHSA-fppq-mj76-fpj2 has a CVSS score of 3.1/10, rated LOW. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-fppq-mj76-fpj2?

GHSA-fppq-mj76-fpj2 affects the following packages: fluentd (RubyGems). Ecosystems affected: RubyGems.

How do I fix GHSA-fppq-mj76-fpj2?

Update fluentd to 1.15.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-fppq-mj76-fpj2 is resolved across your whole dependency graph.

How do I detect GHSA-fppq-mj76-fpj2 in my RubyGems dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for fluentd, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-fppq-mj76-fpj2 if there is no patch (or I can't update yet)?

Do not deserialise data from untrusted sources: where the format allows it, restrict deserialisation to an explicit allowlist of expected types, and prefer a data-only format (JSON, Protobuf) over one that can reconstruct arbitrary objects until you can upgrade.

Is GHSA-fppq-mj76-fpj2 actively exploited in the wild?

No public exploit code has been indexed for GHSA-fppq-mj76-fpj2 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-fppq-mj76-fpj2?

GHSA-fppq-mj76-fpj2 has an EPSS (Exploit Prediction Scoring System) score of 45.0%, placing it in the 99th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score warrants monitoring and prompt remediation.

What type of vulnerability is GHSA-fppq-mj76-fpj2?

GHSA-fppq-mj76-fpj2 is classified as Deserialization of Untrusted Data (CWE-502). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was GHSA-fppq-mj76-fpj2 published, and has it been updated?

GHSA-fppq-mj76-fpj2 was published on November 2, 2022 and was last updated on February 21, 2024. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

💎

💎 RubyGems

Not in CISA KEV

LOW severity

fluentd vulnerable to remote code execution due to insecure deserialization (in non-default configuration)GHSA-fppq-mj76-fpj2

LOWFix: fluent/fluentd@48e5b85

GHSA-fppq-mj76-fpj2 is a low-severity (CVSS 3.1) Deserialization of Untrusted Data vulnerability in fluentd. EPSS puts its 30-day exploitation probability at 45.0% (99th percentile). A fix is available for fluentd — see the affected versions and patch details below.

Also known asBIT-fluentd-2022-39379CVE-2022-39379

Published

Nov 2, 2022

Updated

Feb 21, 2024

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 6, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for GHSA-fppq-mj76-fpj2.

EPSS Exploitation Probability

via FIRST.org ↗

45.0%probability of exploitation in next 30 days

High Risk0.00%

Lower risk than most CVEs99th percentile — riskier than 99% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected

💎fluentd

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects RubyGems packages — download data is not available via public APIs for these ecosystems.

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.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
💎RubyGems	`fluentd`	≥ 1.13.2&&< 1.15.3	1.15.3`bundle update fluentd --conservative`

Affected Products

2 products · 2 configurations

fedorafedoraproject

1 version

Application

fluentdfluentd

≥ 1.13.2 && < 1.15.3

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for fluentd, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update fluentd to 1.15.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-fppq-mj76-fpj2 is resolved across your whole dependency graph.
Workarounds
Do not deserialise data from untrusted sources: where the format allows it, restrict deserialisation to an explicit allowlist of expected types, and prefer a data-only format (JSON, Protobuf) over one that can reconstruct arbitrary objects until you can upgrade.

Frequently Asked Questions

### Impact 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. ### Patches v1.15.3 ### Workarounds Do not use `FLUENT_OJ_OPTION_MODE=object`. ### References * GHSL-2022-067