CustomTCP
Hunt this family in your stack
Mallory pivots from this family to the IOCs, detections, and named campaigns that touch your stack, and pages you when something new lands.
Vulnerabilities exploited
1 CVE Mallory has correlated with this family across public research and vendor advisories. Each row links to the full Mallory page for that vulnerability.
It is our hypothesis that these legitimate compromised sites were all compromised sometime after early November using CVE-2015-7501 [7,8] and publicly available exploit code [9].
Groups observed using it
2 distinct threat actors attributed by public researchers. Open in Mallory to see the full evidence chain and overlapping campaigns.
Several items of importance were located in this archive... a custom Trojan (aka, CustomTCP) that beacons to port 22... The CustomTCP Trojan was covered in a recent article and tentatively attributed to C0d0s0, while also explaining the same similarities we discussed earlier to the November 2014 Forbes watering hole attack.
Several items of importance were located in this archive... a custom Trojan (aka, CustomTCP) that beacons to port 22... The CustomTCP Trojan was covered in a recent article and tentatively attributed to C0d0s0, while also explaining the same similarities we discussed earlier to the November 2014 Forbes watering hole attack.
Techniques & procedures
5 distinct techniques documented for this family, organized by ATT&CK tactic.
Initial Access
1 techniqueIt is our hypothesis that these legitimate compromised sites were all compromised sometime after early November using CVE-2015-7501 and publicly available exploit code.
Execution
2 techniquesSeveral items of importance were located in this archive, including VBS downloaders... Both VBS scripts operate very similarly...
Stealth
1 techniqueCommand and Control
2 techniquesa custom Trojan (aka, CustomTCP) that beacons to port 22
In one instance related to this cluster of activity, we observed Bergard receive instructions from its C2 to retrieve a PNG file containing an encoded PlugX payload... Rekaf supported commands... upload: Download file from C2 ... update: Retrieve an updated payload.
IOCs tracked for this family
23 indicators attributed across vendor reports, sandbox runs, and researcher write-ups. Full values are available in Mallory.
IPs, domains, and DNS infrastructure linked to this family.
File hashes (MD5, SHA-1, SHA-256) from samples and reports.
Recent activity
1 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
The version that knows your environment.
Match every observed IP, domain, and hash against your live telemetry.
Named campaigns wielding this family, with evidence pinned to each claim.
CVEs this family uses for access and lateral movement.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Every documented technique, ranked by evidence weight.
Reddit, Mastodon, and CTI community discussion around this family.