Loading threat actor…
UNC5221, also tracked as UTA0178, is a China-linked cyberespionage threat actor active since at least December 2023. Its operations emphasize exploitation of internet-facing VPN gateways and other edge appliances to obtain stealthy, long-term access and steal credentials and sensitive information. The activity cluster formerly tracked as UNC5337, associated with the SPAWN malware ecosystem, was subsequently merged into UNC5221. The actor operates across multiple countries and industries and has targeted technology vendors, including F5, where an intrusion resulted in theft of BIG-IP source code, information about undisclosed vulnerabilities, and some customer configuration information. UNC5221 exploited the Ivanti Connect Secure authentication-bypass vulnerability CVE-2023-46805 and command-injection vulnerability CVE-2024-21887 as zero-days beginning in December 2023, subsequently expanding exploitation after public disclosure. Its exploitation history also includes Ivanti CVE-2025-0282, CVE-2025-22457, and zero-day exploitation of CVE-2023-4966 affecting Citrix NetScaler appliances. It has also been linked to exploitation of SAP NetWeaver vulnerability CVE-2025-31324. Its tooling includes the ZIPLINE passive backdoor, LIGHTWIRE and GIFTEDVISITOR webshells, WARPWIRE and DRYHOOK credential harvesters, PHASEJAM, and the SPAWN ecosystem. SPAWN components provide persistent installation, SSH backdoor access, tunneling, process injection, and log suppression. TRAILBLAZE and BRUSHFIRE provide in-memory payload deployment and passive backdoor functionality. Post-exploitation activities include network reconnaissance, credential collection, configuration extraction, data staging and exfiltration, and lateral movement. Defense evasion includes trojanizing legitimate appliance components, manipulating integrity checks and stored hashes, deleting logs and forensic artifacts, and interfering with legitimate upgrades. UNC5221 also uses compromised network appliances and routers as an obfuscation network to conceal intrusion origins.
Mallory correlates actor tradecraft and target patterns against your stack, your sector, and your geography. See overlap before they land.
Who, where, and (when attributed) which flag flies behind the operation. Pulled from open-source reporting and Mallory's analyst review.
Sectors the actor has been observed targeting.
Geographies tied to known operations.
Attributed origin per open-source reporting.
57 distinct techniques observed across reporting, grouped by tactic. Hover any cell for the evidence excerpt; click through for MITRE's full description.
35 malware families attributed to this actor across reporting.
30 additional families tracked in Mallory.
21 CVEs this actor has used in observed campaigns. 21 of them exploited in the wild.
GTIG has previously reported UNC5221 conducting zero-day exploitation of CVE-2025-0282, as well as the exploitation CVE-2023-46805 and CVE-2024-21887.
GTIG has previously reported UNC5221 conducting zero-day exploitation of CVE-2025-0282, as well as the exploitation CVE-2023-46805 and CVE-2024-21887.
GTIG has previously reported UNC5221 conducting zero-day exploitation of CVE-2025-0282.
The earliest evidence of observed CVE-2025-22457 exploitation occurred in mid-March 2025. Following successful exploitation, we observed the deployment of two newly identified malware families, the TRAILBLAZE in-memory only dropper and the BRUSHFIRE passive backdoor.
Vendors additionally document KrustyLoader delivery through exploitation of specific internet-facing vulnerabilities, including the following: SAP NetWeaver (CVE-2025-31324)
16 more CVEs tied to this actor tracked in Mallory.
163 indicators attributed to this actor: domains, IPs, hashes, and other artifacts pulled from reporting. View more in app.
20 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
Referenced as a Chinese espionage group previously observed exploiting SAP product vulnerabilities, specifically CVE-2025-31324 affecting SAP products including SAP NetWeaver.
Mentioned as a China-linked APT group that previously exploited critical SAP flaws; not tied to the current CVE-2026-58231 exploitation in this article.
Referenced as a China-nexus espionage cluster previously observed weaponizing SAP product flaws including CVE-2025-31324.
Chinese-linked actor using zero-day vulnerabilities in espionage-oriented operations to steal valuable information from government agencies and private companies.
Match sector + geo + tech-stack targeting against your real footprint.
Every observed MITRE ATT&CK technique, grouped by tactic.
Families this actor is known to deploy, with IOCs and behavior.
CVEs this actor has used in known campaigns.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Domains, IPs, and hashes tied to this actor, refreshed continuously.