CVE-2021-31559

S2S TcpToken authentication bypass

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Published May 6, 2022 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Description

A crafted request bypasses S2S TCP Token authentication writing arbitrary events to an index in Splunk Enterprise Indexer 8.1 versions before 8.1.5 and 8.2 versions before 8.2.1. The vulnerability impacts Indexers configured to use TCPTokens. It does not impact Universal Forwarders.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Splunk

Splunk Enterprise

affected

Version	Status	Constraints
`8.2 version(s) before 8.2.1`	affected	—
`Version(s) before 8.1.5`	affected	—

Configuration 1 [-]

OR	cpe:2.3:a:splunk:splunk:::::enterprise:::*
	cpe:2.3:a:splunk:splunk:8.2.0::::enterprise:::

No data.

No data available yet.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source	ID	Title
EUVD	EUVD-2021-18456	A crafted request bypasses S2S TCP Token authentication writing arbitrary events to an index in Splunk Enterprise Indexer 8.1 versions before 8.1.5 and 8.2 versions before 8.2.1. The vulnerability impacts Indexers configured to use TCPTokens. It does not impact Universal Forwarders.

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact High

Availability Impact None

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication None

Confidentiality Impact None

Integrity Impact Partial

Availability Impact None

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.892% probability within 30 days)

Key SSVC decision points have not yet been added.

References

Link	Providers
https://www.splunk.com/en_us/product-security/announcements/svd-2022-0503.html

History

No history.

Subscriptions

Splunk Splunk

Weaknesses

Sources

CVE record Updated: Aug 3, 2024, 11:03 PM

Status: PUBLISHED
Assigner: Splunk
Published: May 6, 2022, 4:35 PM
Updated: Aug 3, 2024, 11:03 PM
Reserved: Nov 3, 2021, 12:00 AM

View source JSON

Vulnrichment No data

No data.

NVD Updated: Jun 17, 2026, 3:52 AM

Status: Modified
Published: May 6, 2022, 5:15 PM
Modified: Jun 17, 2026, 3:52 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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