CVE-2021-31559

S2S TcpToken authentication bypass

HIGH

7.5

CVSS Score

Published: May 6, 2022 at 04:35 PM UTC

Updated: June 17, 2026 at 03:52 AM UTC

1 product affected across 1 vendorSplunk

Using Splunk Enterprise by Splunk?

Get instant alerts when new vulnerabilities affect Splunk Enterprise - before attackers find them.

Real-time alertsTrack your software stackFree plan available

Start Free Sign In

Severity

HIGH7.5

Exploit prediction

EPSS 0.9%

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

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Splunk · Splunk

95%

v < 8.1.5v < 8.2.18.1.0 ≤ v < 8.1.58.2.0

Affected range stops below 8.1.5, so it looks safe — our inference, not a vendor statement

Affected range stops below 8.2.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

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

References (1)

x_refsource_MISCVendor Advisory

Source: [email protected]

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

CVSS

7.5HIGHSplunk

Attack Vector: NETWORK
Complexity: LOW
Privileges: NONE
User Interaction: NONE
Scope: UNCHANGED
Confidentiality: NONE
Integrity: HIGH
Availability: NONE

Vector?

Quick Info

StatusMODIFIED

CWE

CWE-288NVD-CWE-noinfo

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Create account Sign in

Free plan, no card