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Mentions the CVE; no further detail.
CVE-2021-22893 KEVRansomwarePublic exploit Critical · 10.0 EPSS 47.2%
Ivanti Pulse Connect Secure Use-After-Free Vulnerability
Ivanti · Pulse Connect Secure
Summary
The flaw is an authentication bypass in the Windows File Share Browser and Pulse Secure Collaboration features of Ivanti Pulse Connect Secure, affecting version 9.0R3/9.1R1 and higher. Remote, unauthenticated attackers can exploit it over the network without credentials or user interaction to achieve arbitrary code execution on the Pulse Connect Secure gateway.
Official description · NVD
Pulse Connect Secure 9.0R3/9.1R1 and higher is vulnerable to an authentication bypass vulnerability exposed by the Windows File Share Browser and Pulse Secure Collaboration features of Pulse Connect Secure that can allow an unauthenticated user to perform remote arbitrary code execution on the Pulse Connect Secure gateway. This vulnerability has been exploited in the wild.
Priority scorePatchfirst’s 0 to 100 ranking. It adds points for CISA KEV listing, ransomware use, EPSS, threat reports, public exploit code and CVSS. Every CVE page shows the breakdown. Breakdown
83.6 / 100
- Exploited
- Yes, in CISA KEV
- Reports
- 1
- Tactics
- 3/15
How an attack unfolds
Based on MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. mappings. Select a step to see the evidence.Exploitation timelineDated milestones for a CVE: when it was disclosed, when exploit code became public, when exploitation was confirmed, and when threat reports named it.
First seen exploited 3 days before it was disclosed. Public exploit code (PoC-in-GitHub) was available 2 days before disclosure.
- First seen exploitedVulnCheck KEV evidence3 days before
- Public exploit codePoC-in-GitHub2 days before
- Disclosedday 0
- Added to CISA KEVknown ransomware use; EU database agrees+6 mo
- Named in a threat reportmicrosoft.com+13 mo
CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.
MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. techniques
3 TechniqueOne specific attacker behaviour in MITRE ATT&CK, such as T1190 “Exploit Public-Facing Application”. IDs with a dot, like T1059.004, are sub-techniques., grouped by TacticThe attacker’s goal at a stage of an attack in MITRE ATT&CK, such as Initial Access or Persistence. Each technique belongs to one or more tactics. in kill-chain order 3Initial AccessTA0001
MITRE CTID mapping of the KEV entry · how it is exploited
This vulnerability is exploited through an authentication bypass weakness in the Windows File Share Browser and Pulse Secure Collaboration features of Pulse Connect Secure. Remote attackers leverage this vulnerability to perform remote arbitrary code execution on the Pulse Connect Secure gateway by bypassing authentication controls. The threat actor group UNC2630 has utilized this flaw to harvest login credentials, allowing them to move laterally within affected environments.
ExecutionTA0002
MITRE CTID mapping of the KEV entry · primary impact
Credential AccessTA0006
OS Credential Dumping T1003
MITRE CTID mapping of the KEV entry · follow-on activity
Detection
1 rule for this CVE · 281 general rules for its techniquesRules for this CVE
1Sigma ruleAn open, vendor-neutral detection rule for log data. Security teams convert Sigma rules into searches for their own SIEM. that reference CVE-2021-22893 directly.General rules for this CVE’s techniques
These detect the technique in general, not this specific vulnerability.
Exploit Public-Facing ApplicationT1190149 general rules
- Arcadyan Router Exploitationscriticaltest
- Citrix ADS Exploitation CVE-2020-8193 CVE-2020-8195criticaltest
- Citrix Netscaler Attack CVE-2019-19781criticaltest
- Confluence Exploitation CVE-2019-3398criticaltest
- CVE-2010-5278 Exploitation Attemptcriticaltest
- CVE-2020-0688 Exchange Exploitation via Web Logcriticaltest
- CVE-2020-10148 SolarWinds Orion API Auth Bypasscriticaltest
- CVE-2020-5902 F5 BIG-IP Exploitation Attemptcriticaltest
Command and Scripting InterpreterT105995 general rules
- HackTool - Sliver C2 Implant Activity Patterncriticaltest
- Lazarus Group Activitycriticaltest
- REvil Kaseya Incident Malware Patternscriticaltest
- Turla Group Lateral Movementcriticaltest
- Windows Defender AMSI Trigger Detectedhighstable
- Windows Defender Threat Detectedhighstable
- Abusable DLL Potential Sideloading From Suspicious Locationhightest
- Add Insecure Download Source To Wingethightest
OS Credential DumpingT100337 general rules
- Antivirus - Password Dumper Signaturecriticalstable
- HackTool - Rubeus Executioncriticalstable
- Hacktool Execution - Imphashcriticaltest
- Potential Credential Dumping Via LSASS Process Clonecriticaltest
- WCE wceaux.dll Accesscriticaltest
- HackTool - Potential Remote Credential Dumping Activity Via CrackMapExec Or Impacket-Secretsdumphightest
- HackTool - Rubeus Execution - ScriptBlockhightest
- Hacktool Execution - PE Metadatahightest
Sigma rules © SigmaHQ, Detection Rule License 1.1; linked, not reproduced.
What security researchers reported
Named in 1 threat report1 reportMicrosoftMay 2022
Reports are matched by finding the exact id CVE-2021-22893 in their text; nobody has reviewed the match. One passage is shown per report, at most 320 characters, linked to the original.
Also mentioned in 50 community threat pulses (AlienVault OTX)
Weaker evidencePulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.
- Actively_Exploited_Kev | Oct 29, 202628 Oct 2026
- Actively_Exploited_Kev | Oct 28, 202627 Oct 2026
- Actively_Exploited_Kev | Oct 27, 202626 Oct 2026
- Actively_Exploited_Kev | Oct 24, 202623 Oct 2026
- Actively_Exploited_Kev | Oct 23, 202622 Oct 2026
- Actively_Exploited_Kev | Oct 22, 202621 Oct 2026
- 44 more on OTX