CVE-2026-54680: Logging operator has Fluentd configuration injection that allows remote code execution

Should you act?

Critical, preconditions apply

Severe if exploited, but exploitation needs conditions that may not apply to you. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• Not in CISA KEV, but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
• EPSS 0.8%, percentile 56: FIRST’s model estimates a 0.8% chance of exploitation activity in the next 30 days, higher than 56% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
• Needs an account (low (any account)). Exposure depends on who can log in.
• Only applies if your dependency tree includes github.com/kube-logging/logging-operator (Go) < 0.0.0-20260608145523-cf437d7f1e05, fixed in 0.0.0-20260608145523-cf437d7f1e05. Check your lockfile, including transitive dependencies.

What it is

Logging operator automates the deployment and configuration of Kubernetes logging pipelines. Prior to 6.6.0, the Fluentd configuration renderer FluentRender in pkg/sdk/logging/model/render/fluent.go writes CRD strings such as Flow recordtransformer.records values directly into fluent.conf without escaping, allowing a user who can create Flow resources to inject a Fluentd block using @type exec and execute arbitrary commands inside the Fluentd aggregator. This issue is fixed in version 6.6.0.

From the GitHub advisory

Summary

The Fluentd configuration renderer in Logging operator writes strings from CRDs such as Flow directly into fluent.conf without escaping them. As a result, a user who can create Flow resources can inject Fluentd configuration by providing values that contain newlines.

In the confirmed path, a value in recordtransformer.records can close the current / block and add a new block. By specifying Fluentd's core @type exec plugin in that injected block, an attacker can execute arbitrary commands inside the Fluentd aggregator.

Details

The issue is in FluentRender in pkg/sdk/logging/model/render/fluent.go.

Weakness type: CWE-74, CWE-77.

Product: github.com/kube-logging/logging-operator (Go) · Assigned by: GitHub_M · Published: 2026-07-29

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: low (any account)
• User interaction: none
• Scope: changed (can affect other components)

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation poc, automatable no, technical impact total.
• FIRST EPSS (model of 2026-10-21): 0.78% probability of exploitation activity in the next 30 days; percentile 56.

Timeline

• 2026-07-29 — CVE record published by GitHub_M
• 2026-07-29 — GitHub-reviewed advisory GHSA-mjqf-28ph-426h published (critical)
• 2026-07-30 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-mjqf-28ph-426h github.com
2. CVE.org record CVE-2026-54680 cve.org
3. NVD entry CVE-2026-54680 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com
2. github.com github.com
3. github.com github.com

Critical Go advisories · Today’s Security Digest