Cisco Secure Firewall - Veeam CVE-2023-27532 Exploitation Activity
Description
This analytic detects exploitation activity of CVE-2023-27532 using Cisco Secure Firewall Intrusion Events.
It leverages Cisco Secure Firewall Threat Defense IntrusionEvent logs to identify cases where Snort signature 61514 (Veeam Backup and Replication credential dump attempt)
is followed within a 5-minute window by 64795 (Veeam Backup and Replication xp_cmdshell invocation attempt), which detects the use of xp_cmdshell, a common post-exploitation technique.
If confirmed malicious, this behavior is highly indicative of a successful exploitation of CVE-2023-27532, followed by remote command execution or credential dumping.
Query · spl
`cisco_secure_firewall` EventType=IntrusionEvent signature_id IN (61514, 64795)
| bin _time span=5m
| fillnull
| stats dc(signature_id) as unique_signature_count
values(signature_id) as signature_id
values(signature) as signature
values(class_desc) as class_desc
values(MitreAttackGroups) as MitreAttackGroups
values(InlineResult) as InlineResult
values(InlineResultReason) as InlineResultReason
values(src) as src
values(dest_port) as dest_port
values(rule) as rule
values(transport) as transport
values(app) as app
min(_time) as firstTime
max(_time) as lastTime
by dest
| where unique_signature_count = 2
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `cisco_secure_firewall___veeam_cve_2023_27532_exploitation_activity_filter`
Implementation guide
This search requires Cisco Secure Firewall Threat Defense Logs, which
includes the IntrusionEvent EventType. This search uses an input macro named cisco_secure_firewall.
We strongly recommend that you specify your environment-specific configurations
(index, source, sourcetype, etc.) for Cisco Secure Firewall Threat Defense logs. Replace the macro definition
with configurations for your Splunk environment. The search also uses a post-filter
macro designed to filter out known false positives.
The logs are to be ingested using the Splunk Add-on for Cisco Security Cloud (https://splunkbase.splunk.com/app/7404).
The intrusion access policy must also be configured.
Known false positives
- False positives should be very unlikely.
Analyst notes
Known false positives: False positives should be very unlikely.