Coverage › CVE-2025-54309
CVE-2025-54309 Mapped Sigma
CrushFTP Unprotected Alternate Channel Vulnerability
- Vendor / product
- CrushFTP — CrushFTP
- Description (CISA)
- CrushFTP contains an unprotected alternate channel vulnerability. When the DMZ proxy feature is not used, mishandles AS2 validation and consequently allows remote attackers to obtain admin access via HTTPS.
- Added to KEV
- 2025-07-22
- Due date
- 2025-08-12
- Required action
- Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- Known ransomware use
- Unknown
- CWE
- CWE-420
- CISA notes
- https://www.crushftp.com/crush11wiki/Wiki.jsp?page=CompromiseJuly2025
https://nvd.nist.gov/vuln/detail/CVE-2025-54309 - Elsewhere
- cve.org · NVD · CISA KEV · JSON
ATT&CK techniques · CTID Mappings Explorer, ATT&CK 16.1, KEV snapshot 2025-07-28
3 mapping objects across 3 techniques. exploitation technique states how the vulnerability is exploited; primary and secondary impact state what exploitation achieves. They are different claims and are labelled as such.
| Technique | Mapping type | CTID comment | Status in v19.2 |
|---|---|---|---|
| T1068 Exploitation for Privilege Escalation | exploitation technique | Improper validation of AS2 messages in CrushFTP without DMZ proxy enabled were reported to be exploited to bypass authentication and gain administrative access over HTTPS, leading to system compromise, data exfiltration, and lateral movement. ref 1 · ref 2 |
live |
| T1021 Remote Services | secondary impact | Improper validation of AS2 messages in CrushFTP without DMZ proxy enabled were reported to be exploited to bypass authentication and gain administrative access over HTTPS, leading to system compromise, data exfiltration, and lateral movement. ref 1 · ref 2 |
live |
| T1567 Exfiltration Over Web Service | primary impact | Improper validation of AS2 messages in CrushFTP without DMZ proxy enabled were reported to be exploited to bypass authentication and gain administrative access over HTTPS, leading to system compromise, data exfiltration, and lateral movement. ref 1 · ref 2 |
live |
Detection chain · ATT&CK Enterprise v19.2 detection strategies, analytics, log sources
T1021 Remote Services secondary impact
- DET0269 Behavioral Detection Strategy for Remote Service Logins and Post-Access Activity
AN0750 WindowsLogon via RDP or WMI by a user account followed by uncommon command execution, file manipulation, or lateral network connections.Tunable:
TimeWindowLogonUserRemoteHostListAN0751 LinuxSSH session from new source IP followed by interactive shell or privilege escalation (e.g., sudo, su) and outbound lateral connection.Tunable:SourceIPCommandListAN0752 macOSRemote login via ARD or SSH followed by screensharingd process activity or modification of TCC-protected files.macos:unifiedlogeventMessage CONTAINS 'screensharingd' or 'AuthorizationRefCreate'→ DC0067 Logon Session CreationTunable:RemoteServiceTargetedPathAN0753 IaaSUse of cloud-based bastion or VM console session followed by commands that initiate outbound SSH or RDP sessions from the cloud instance to other environments.Tunable:SourceAssetTagTargetPortListAN0754 ESXivSphere API logins (vimService) or SSH to ESXi host followed by unauthorized shell commands or lateral remote logins from the ESXi host.Tunable:SessionTypeCommandPattern
Sigma rules tagged attack.t1021 (11)
Author: Security Onion Solutions
· 2024-03-08 · logsource: product=opencanary category=application · 22777c9e-873a-4b49-855f-6072ab861a52
Detects instances where an SMB service on an OpenCanary node has had a file open request.
Author: Security Onion Solutions
· 2024-03-08 · logsource: product=opencanary category=application · 6991bc2b-ae2e-447f-bc55-3a1ba04c14e5
Detects instances where an FTP service on an OpenCanary node has had a login attempt.
Author: omkar72
· 2020-10-30 (modified 2023-02-28) · logsource: product=windows category=process_creation · 730fc21b-eaff-474b-ad23-90fd265d4988
Detects user accept agreement execution in psexec commandline
Author: Chirag Damani
· 2026-03-29 · logsource: product=windows category=process_creation · 7638e5fe-600c-4289-a968-f49dd537ec7d
Detects execution of the hacktool NetExec.
NetExec (formerly CrackMapExec) is a widely used post-exploitation tool designed for Active Directory penetration testing and network enumeration
In enterprise environments, the use of NetExec is considered suspicious or potentially malicious because it enables attackers to enumerate hosts, exploit network services, and move laterally across systems.
Threat actors and red teams commonly use NetExec to identify vulnerable systems, harvest credentials, and execute commands remotely.
Author: Tim Rauch, Elastic (idea)
· 2022-09-27 · logsource: product=windows category=process_creation · 8a3038e8-9c9d-46f8-b184-66234a160f6f
Detects potential use of an SSH utility to establish RDP over a reverse SSH Tunnel. This can be used by attackers to enable routing of network packets that would otherwise not reach their intended destination.
Author: Tim Rauch, Elastic (idea)
· 2022-09-27 (modified 2022-12-30) · logsource: product=windows category=process_creation · 9bd04a79-dabe-4f1f-a5ff-92430265c96b
Detects a remote file copy attempt to a hidden network share. This may indicate lateral movement or data staging activity.
Author: Security Onion Solutions
· 2024-03-08 · logsource: product=opencanary category=application · 9db5446c-b44a-4291-8b89-fcab5609c3b3
Detects instances where a VNC service on an OpenCanary node has had a connection attempt.
Author: Security Onion Solutions
· 2024-03-08 · logsource: product=opencanary category=application · cd55f721-5623-4663-bd9b-5229cab5237d
Detects instances where an SSH service on an OpenCanary node has had a connection attempt.
Author: Security Onion Solutions
· 2024-03-08 · logsource: product=opencanary category=application · e9856028-fd4e-46e6-b3d1-10f7ceb95078
Detects instances where an SNMP service on an OpenCanary node has had an OID request.
Author: Josh Nickels
· 2024-05-10 · logsource: product=windows category=network_connection · fda34293-718e-4b36-b018-38caab0d1209
Detects an RDP connection originating from a domain controller.
Author: Security Onion Solutions
· 2024-03-08 · logsource: product=opencanary category=application · ff7139bc-fdb1-4437-92f2-6afefe8884cb
Detects instances where an SSH service on an OpenCanary node has had a login attempt.
T1068 Exploitation for Privilege Escalation exploitation technique
- DET0514 Detection Strategy for Exploitation for Privilege Escalation
AN1419 WindowsDetects exploitation attempts targeting vulnerable kernel drivers or OS components, often followed by unusual process or token behavior.Tunable:
DriverNamePatternTimeWindowParentProcessPathAN1420 LinuxDetects escalation via vulnerable setuid binaries or kernel modules, often chained with unusual access to /proc/kallsyms or /dev/kmem.Tunable:SetUIDBinaryListTimeWindowEffectiveUIDThresholdAN1421 macOSDetects use of vulnerable kernel extensions or entitlements abused via setuid or AppleScript injection chains.Tunable:EntitlementListTimeWindowAN1422 ContainersDetects container breakout behavior via exploitation (e.g., DirtyPipe, CVE-2022-0847), followed by host OS interaction or escalated capability assignment.Tunable:NamespaceEscapePatternTimeWindow
Sigma rules tagged attack.t1068 (31)
Author: Florian Roth (Nextron Systems)
· 2019-11-20 (modified 2024-12-01) · logsource: product=windows category=process_creation · 02e0b2ea-a597-428e-b04a-af6a1a403e5c
Detects an exploitation attempt in which the UAC consent dialogue is used to invoke an Internet Explorer process running as LOCAL_SYSTEM
Author: Nasreddine Bencherchali (Nextron Systems)
· 2022-08-18 (modified 2023-12-02) · logsource: product=windows category=driver_load · 05296024-fe8a-4baf-8f3d-9a5f5624ceb2
Detects loading of known malicious drivers via their hash.
Author: Florian Roth (Nextron Systems)
· 2021-10-09 (modified 2022-12-25) · logsource: product=linux service=auditd · 071d5e5a-9cef-47ec-bc4e-a42e34d8d0ed
Detects command line parameter very often used with coin miners
Author: Nisarg Suthar
· 2025-08-01 · logsource: product=windows category=process_creation · 0fdc7c7f-c690-4217-9ae3-31f5156eed72
Detects suspicious child processes created by CrushFTP. It could be an indication of exploitation of a RCE vulnerability such as CVE-2025-54309.
Author: Swachchhanda Shrawn Poudel (Nextron Systems)
· 2025-10-02 (modified 2026-03-31) · logsource: product=linux category=file_event · 10ac0730-c24e-4f4c-81f8-b13a1ac95a1d
Detects the creation of nsswitch.conf files in non-standard directories, which may indicate exploitation of CVE-2025-32463.
This vulnerability requires an attacker to create a nsswitch.conf in a directory that will be used during sudo chroot operations.
When sudo executes, it loads malicious shared libraries from user-controlled locations within the chroot environment,
potentially leading to arbitrary code execution and privilege escalation.
Author: @eyezuhk Isaac Fernandes
· 2025-02-19 · logsource: product=windows category=image_load · 17ce9373-2163-4a2c-90ba-f91e9ef7a8c1
Detects potentially suspicious loading of "ksproxy.ax", which may indicate an attempt to exploit CVE-2024-35250.
Author: Florian Roth (Nextron Systems)
· 2017-03-01 (modified 2025-03-17) · logsource: product=linux · 18b042f0-2ecd-4b6e-9f8d-aa7a7e7de781
Detects buffer overflow attempts in Unix system log files
Author: Florian Roth (Nextron Systems), oscd.community, Jonhnathan Ribeiro
· 2019-11-15 (modified 2021-11-27) · logsource: product=windows category=process_creation · 1c373b6d-76ce-4553-997d-8c1da9a6b5f5
Detects exploitation attempt of privilege escalation vulnerability via SetupComplete.cmd and PartnerSetupComplete.cmd described in CVE-2019-1378
Author: Roberto Rodriguez (Cyb3rWard0g), OTR (Open Threat Research), MSTIC
· 2021-10-15 (modified 2022-10-05) · logsource: product=linux category=process_creation · 21541900-27a9-4454-9c4c-3f0a4240344a
Rule to detect the use of the SCX RunAsProvider Invoke_ExecuteShellCommand to execute any UNIX/Linux command using the /bin/sh shell.
SCXcore, started as the Microsoft Operations Manager UNIX/Linux Agent, is now used in a host of products including
Microsoft Operations Manager, Microsoft Azure, and Microsoft Operations Management Suite.
Author: Swachchhanda Shrawan Poudel (Nextron Systems)
· 2025-06-06 · logsource: product=windows category=process_creation · 38a1ac5f-9c74-47d2-a345-dd6f5eb4e7c8
Detects the execution of SharpSuccessor, a tool used to exploit the BadSuccessor attack for privilege escalation in WinServer 2025 Active Directory environments.
Successful usage of this tool can let the attackers gain the domain admin privileges by exploiting the BadSuccessor vulnerability.
Author: Nasreddine Bencherchali (Nextron Systems)
· 2022-10-03 (modified 2023-12-02) · logsource: product=windows category=driver_load · 39b64854-5497-4b57-a448-40977b8c9679
Detects loading of known malicious drivers via the file name of the drivers.
Author: Florian Roth (Nextron Systems)
· 2021-11-22 (modified 2022-12-25) · logsource: product=windows category=file_event · 3be82d5d-09fe-4d6a-a275-0d40d234d324
Detects signs of the exploitation of LPE CVE-2021-41379 that include an msiexec process that creates an elevation_service.exe file
Author: Gene Kazimiarovich
· 2026-04-30 · logsource: product=linux service=auditd · 474b415a-8b3d-4e6a-9f12-0d5c8a7b6e94
Detects creation of AF_ALG (Address Family 38) sockets via the socket() syscall.
AF_ALG is the Linux kernel crypto API interface. It is exploited in CVE-2026-31431
to achieve local privilege escalation via a buffer overflow in the AF_ALG AEAD
splice path that corrupts the page cache of SUID binaries.
Legitimate AF_ALG usage is rare and confined to specific crypto utilities and VPN
daemons using non-default kernel offload configurations.
Author: Gene Kazimiarovich
· 2026-05-09 · logsource: product=linux category=process_creation · 474b415a-d917-4f3b-8c62-9e1a0d5f7b48
Detects kernel auto-loading of the authencesn crypto module via modprobe
This occurs when user-space code creates an AF_ALG socket and binds the authencesn AEAD cipher
(e.g., authencesn(hmac(sha256),cbc(aes))). The kernel invokes modprobe to load the
crypto module. This is a key indicator of CVE-2026-31431 (Copy Fail) exploitation,
where the authencesn cipher is used to trigger a buffer overflow in the AF_ALG AEAD splice path,
corrupting the page cache of SUID binaries for local privilege escalation.
On Linux systems, modprobe is typically a symlink to kmod, so the process image will be /usr/bin/kmod (or /bin/kmod)
with 'modprobe' appearing in the command line.
Author: Florian Roth (Nextron Systems), Zach Mathis
· 2020-01-15 (modified 2022-10-22) · logsource: product=windows service=application · 48d91a3a-2363-43ba-a456-ca71ac3da5c2
Detects events generated by user-mode applications when they call the CveEventWrite API when a known vulnerability is trying to be exploited.
MS started using this log in Jan. 2020 with CVE-2020-0601 (a Windows CryptoAPI vulnerability.
Unfortunately, that is about the only instance of CVEs being written to this log.
All 31 rules on the technique page →
T1567 Exfiltration Over Web Service primary impact
- DET0548 Detection Strategy for Exfiltration Over Web Service
AN1511 WindowsProcesses that normally do not initiate network communications suddenly making outbound HTTPS connections with high outbound-to-inbound data ratios. Defender view: correlation between process creation logs (e.g., Word, Excel, PowerShell) and subsequent anomalous network traffic volumes toward common web services (Dropbox, Google Drive, OneDrive).Tunable:
MonitoredServicesExfilVolumeThresholdTimeWindowAN1512 LinuxProcesses (tar, curl, python scripts) accessing large file sets and initiating outbound HTTPS POST requests with payload sizes inconsistent with baseline activity. Defender perspective: detect abnormal sequence of file archival followed by encrypted uploads to external web services.Tunable:MonitoredToolsDataVolumeThresholdAN1513 macOSOffice apps or scripts writing files followed by xattr manipulation (to evade quarantine) and subsequent HTTPS uploads. Defender perspective: anomalous file modification + outbound TLS traffic originating from non-networking apps (Word, Excel, Preview).macos:unifiedlogoutbound TLS connections to cloud storage providers→ DC0085 Network Traffic ContentTunable:WatchedApplicationsAN1514 SaaSAbnormal API calls from user accounts invoking file upload endpoints outside normal baselines (M365, Google Drive, Box). Defender perspective: monitor unified audit logs for elevated frequency of Upload, Create, or Copy operations from compromised accounts.Tunable:APICallThresholdUserBaselineProfilesAN1515 ESXiESXi guest OS or management interface processes establishing unexpected external HTTPS connections. Defender perspective: monitor vmx or hostd processes making outbound web requests with significant data transfer.esxi:vmkernelnetwork session initiation with external HTTPS services→ DC0082 Network Connection CreationTunable:DatastoreTransferThreshold
Sigma rules tagged attack.t1567 (12)
Author: Nasreddine Bencherchali (Nextron Systems), Cedric MAURUGEON (Update)
· 2022-09-15 (modified 2023-05-02) · logsource: product=linux category=process_creation · 00b90cc1-17ec-402c-96ad-3a8117d7a582
Detects a suspicious curl process start the adds a file to a web request
Author: Florian Roth (Nextron Systems), Cedric MAURUGEON (Update)
· 2020-07-03 (modified 2023-05-02) · logsource: product=windows category=process_creation · 00bca14a-df4e-4649-9054-3f2aa676bc04
Detects the execution of the "curl" process with "upload" flags. Which might indicate potential data exfiltration
Author: Florian Roth (Nextron Systems)
· 2022-07-16 (modified 2025-07-30) · logsource: product=windows category=network_connection · 18249279-932f-45e2-b37a-8925f2597670
Detects an executable initiating a network connection to "ngrok" domains.
Attackers were seen using this "ngrok" in order to store their second stage payloads and malware.
While communication with such domains can be legitimate, often times is a sign of either data exfiltration by malicious actors or additional download.
Author: Florian Roth (Nextron Systems)
· 2022-11-03 · logsource: product=linux category=network_connection · 19bf6fdb-7721-4f3d-867f-53467f6a5db6
Detects an executable accessing an ngrok tunneling endpoint, which could be a sign of forbidden exfiltration of data exfiltration by malicious actors
Author: Florian Roth (Nextron Systems)
· 2022-11-03 (modified 2024-02-02) · logsource: product=windows category=network_connection · 1d08ac94-400d-4469-a82f-daee9a908849
Detects an executable initiating a network connection to "ngrok" tunneling domains.
Attackers were seen using this "ngrok" in order to store their second stage payloads and malware.
While communication with such domains can be legitimate, often times is a sign of either data exfiltration by malicious actors or additional download.
Author: frack113
· 2021-11-26 (modified 2022-05-16) · logsource: product=windows category=process_creation · 1f0f6176-6482-4027-b151-00071af39d7e
Detects the execution of "ConfigSecurityPolicy.EXE", a binary part of Windows Defender used to manage settings in Windows Defender.
Users can configure different pilot collections for each of the co-management workloads.
It can be abused by attackers in order to upload or download files.
Author: Kamran Saifullah
· 2023-11-20 · logsource: product=windows category=network_connection · 4b657234-038e-4ad5-997c-4be42340bce4
Detects network connections to Visual Studio Code tunnel domains initiated by a process on a system. Attackers can abuse that feature to establish a reverse shell or persistence on a machine.
Author: Kamran Saifullah, Nasreddine Bencherchali (Nextron Systems)
· 2024-05-27 · logsource: product=windows category=network_connection · 7cd1dcdc-6edf-4896-86dc-d1f19ad64903
Detects network connections to Cloudflared tunnels domains initiated by a process on the system.
Attackers can abuse that feature to establish a reverse shell or persistence on a machine.
Author: Kamran Saifullah
· 2024-09-13 · logsource: product=windows category=network_connection · 9e02c8ec-02b9-43e8-81eb-34a475ba7965
Detects network connections to BTunnels domains initiated by a process on the system.
Attackers can abuse that feature to establish a reverse shell or persistence on a machine.
Author: Florian Roth (Nextron Systems)
· 2021-10-24 · logsource: category=dns · b593fd50-7335-4682-a36c-4edcb68e4641
Detects suspicious DNS queries to Monero mining pools
Author: Nasreddine Bencherchali (Nextron Systems)
· 2023-05-19 · logsource: product=windows category=network_connection · c3dbbc9f-ef1d-470a-a90a-d343448d5875
Detects an a non-browser process interacting with the Telegram API which could indicate use of a covert C2
Author: Ialle Teixeira @teixeira0xfffff, Austin Songer @austinsonger
· 2021-09-30 (modified 2022-05-16) · logsource: product=windows category=process_creation · e290b10b-1023-4452-a4a9-eb31a9013b3a
Detects when a user performs data exfiltration by using DataSvcUtil.exe
Sigma rules tagged with this CVE directly
1 rule carries cve.2025-54309.
Author: Nisarg Suthar
· 2025-08-01 · logsource: product=windows category=process_creation · 0fdc7c7f-c690-4217-9ae3-31f5156eed72
Detects suspicious child processes created by CrushFTP. It could be an indication of exploitation of a RCE vulnerability such as CVE-2025-54309.