High severity · published May 6, 2022
CVE-2021-31559
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
7.5
CVSS
0.9%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 59% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SP
Splunk · Splunk
8.1.0 before 8.1.5; 8.2.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-31559
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-31559
Vendor Advisory
https://www.splunk.com/en_us/product-security/announcements/svd-2022-0503.html
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