STEADYPULSE is a web shell used in compromises of Pulse Connect Secure VPN appliances. It is implemented by modifying a legitimate Perl CGI script on the appliance to add a covert command-execution capability, allowing attackers to run arbitrary commands on compromised web servers. Observed behavior indicates the implant can transmit URL-encoded data over command-and-control channels and is triggered through a secret parameter value embedded in the altered script logic.
STEADYPULSE was identified among multiple malware families deployed during intrusions exploiting Pulse Secure vulnerabilities, including activity associated with broader campaigns against defense, government, and financial organizations. It has not been conclusively linked to a specific threat cluster, although it appeared in the same ecosystem of tooling used during the Pulse Secure appliance compromises tracked in 2020 and 2021. The malware is part of a larger post-exploitation toolkit focused on persistence, credential access, authentication bypass, command execution, and operational concealment on edge infrastructure.
The implant targets Pulse Connect Secure appliances running Perl-based web components on a Linux-based platform. Its role is consistent with post-compromise access maintenance and remote administration of the appliance after initial exploitation of exposed VPN infrastructure.
Mallory pivots from this family to the IOCs, detections, and named campaigns that touch your stack, and pages you when something new lands.
4 CVEs Mallory has correlated with this family across public research and vendor advisories. Each row links to the full Mallory page for that vulnerability.
These attacks include using known vulnerabilities from 2019 and 2020 (CVE-2019-11510, CVE-2020-8243, and CVE-2020-8260) and a previously unknown authentication bypass vulnerability tracked as CVE-2021-22893. | Mandiant reported that twelve (12) malware families were used against organizations that were victim of the PCS attacks, including: ATRIUM, HARPULSE, LOCKPICK, PACEMAKER, PULSECHECK, PULSEJUMP, QUIETPULSE, RADIALPULSE, SLIGHTPULSE, SLOWPULSE, STEADYPULSE, and THINBLOOD.
On April 20, 2021, Mandiant reported that previously known PCS vulnerabilities (CVE-2019-11510, CVE-2020-8243, CVE-2020-8260) and a zero-day (CVE-2021-22893) were exploited as early as August 2020, and some activity was still observed through March 2021. | Mandiant reported that twelve (12) malware families were used against organizations that were victim of the PCS attacks, including: ATRIUM, HARPULSE, LOCKPICK, PACEMAKER, PULSECHECK, PULSEJUMP, QUIETPULSE, RADIALPULSE, SLIGHTPULSE, SLOWPULSE, STEADYPULSE, and THINBLOOD.
On April 20, 2021, Mandiant reported that previously known PCS vulnerabilities (CVE-2019-11510, CVE-2020-8243, CVE-2020-8260) and a zero-day (CVE-2021-22893) were exploited as early as August 2020, and some activity was still observed through March 2021. | Mandiant reported that twelve (12) malware families were used against organizations that were victim of the PCS attacks, including: ATRIUM, HARPULSE, LOCKPICK, PACEMAKER, PULSECHECK, PULSEJUMP, QUIETPULSE, RADIALPULSE, SLIGHTPULSE, SLOWPULSE, STEADYPULSE, and THINBLOOD.
On April 20, 2021, Mandiant reported that previously known PCS vulnerabilities (CVE-2019-11510, CVE-2020-8243, CVE-2020-8260) and a zero-day (CVE-2021-22893) were exploited as early as August 2020, and some activity was still observed through March 2021. | Mandiant reported that twelve (12) malware families were used against organizations that were victim of the PCS attacks, including: ATRIUM, HARPULSE, LOCKPICK, PACEMAKER, PULSECHECK, PULSEJUMP, QUIETPULSE, RADIALPULSE, SLIGHTPULSE, SLOWPULSE, STEADYPULSE, and THINBLOOD.
12 distinct techniques documented for this family, organized by ATT&CK tactic.
CVE-2020-8243 (CVSS: 7.2) ... An unauthenticated threat actor could upload a customer template to perform arbitrary code execution. ... CVE-2020-8260 (CVSS: 7.2) ... an unauthenticated threat could execute arbitrary code due to a vulnerability in the admin web interface.
The content repeatedly describes threat actors, malware, and campaigns using HTTP and/or HTTPS for command and control, including examples such as BlackEnergy communicating with C2 over HTTP POST requests and many other families using HTTP/S for C2.
2 indicators attributed across vendor reports, sandbox runs, and researcher write-ups. Full values are available in Mallory.
File hashes (MD5, SHA-1, SHA-256) from samples and reports.
8 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
Custom malware strain deployed during Pulse Secure VPN intrusions; not linked to a specific threat cluster in the cited reporting.
Modified Perl CGI (licenseserverproto.cgi) webshell that executes commands when a secret key is provided (serverid), parsing cmd from QUERY_STRING and returning output via the web interface.
Malware that can transmit URL-encoded data over command-and-control channels.
Malware that transmits URL-encoded data over command-and-control channels.
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.