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Status published
High
CVE-2021-31559
S2S TcpToken authentication bypass
Vulnerability 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.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
No credits recorded in the NVD database.
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Affected Vendor
Splunk
View all reports →Affected Software
Splunk Enterprise
Vulnerable Versions:
8.2 version(s) before 8.2.1, Version(s) before 8.1.5
Timeline
Official Publish:
May 6th, 2022
Last Modified:
August 3rd, 2024
Added to House:
July 21st, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N