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Description

This search detects the heap-based buffer overflow of sudoedit

  • Type: TTP
  • Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
  • Datamodel:
  • Last Updated: 2021-01-29
  • Author: Shannon Davis, Splunk
  • ID: 10f2bae0-bbe6-4984-808c-37dc1c67980d

ATT&CK

ID Technique Tactic
T1068 Exploitation for Privilege Escalation Privilege Escalation
`linux_hosts` 
| search sudoedit segfault 
| stats count min(_time) as firstTime max(_time) as lastTime by host 
| search count > 5 
| `detect_baron_samedit_cve_2021_3156_segfault_filter`

Associated Analytic Story

How To Implement

Splunk Universal Forwarder running on Linux systems (tested on Centos and Ubuntu), where segfaults are being logged. This also captures instances where the exploit has been compiled into a binary. The detection looks for greater than 5 instances of sudoedit combined with segfault over your search time period on a single host

Required field

  • _time
  • host

Kill Chain Phase

  • Exploitation

Known False Positives

If sudoedit is throwing segfaults for other reasons this will pick those up too.

CVE

ID Summary CVSS
CVE-2021-3156 Sudo before 1.9.5p2 contains an off-by-one error that can result in a heap-based buffer overflow, which allows privilege escalation to root via "sudoedit -s" and a command-line argument that ends with a single backslash character. 7.2

Reference

Test Dataset

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

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