Detections
Explore public detection logic contributed by the community across SIEM and rule languages.
31 detections
Filters
Last updated
All Time
Detection languages
15
13
1
1
1
Contributors
10
6
3
2
2
Categories
8
5
5
4
4
Platforms
22
5
2
1
1
Products / Services
11
6
3
2
2
MITRE Techniques
18,110
15,627
12,575
8,387
6,212
CVEs
1
IDS Classtypes
1
IDS Protocols
1
Detects downgrade of network device firmware potentially to reintroduce vulnerabilities
Detects the deletion of a phishing-resistant authentication method (like FIDO2 security key or passkey) followed by the registration of a weaker authentication method (like a phone authentication method or software OATH token) for the same account. This pattern indicates a potential downgrade attack on an account's authentication security.
Detects deletion of a phishing-resistant authentication method followed by registration of a less secure phone or software token method for the same account.
Detects TLS protocol downgrade attacks used to weaken encryption
This rule detects a TLS downgrade attack where a client attempts to establish a connection using a weaker TLS protocol version, specifically TLS 1.0. This could indicate an attacker forcing a less secure communication channel to exploit vulnerabilities in older TLS versions.
Detects action of SSH ertificate Auth being disabled. This would mean password auth is allowed.
This could indicate an Authentication downgrade attack, disabling Security controls.
This could indicate an Authentication downgrade attack, disabling Security controls.
This rule detects attempts to use outdated or weak cryptographic algorithms and protocols by monitoring command-line arguments of common network and cryptographic utilities. Specifically, it looks for the use of RC4, DES, 3DES, RSA1024, MD5 ciphers, or TLS 1.0, TLS 1.1, and SSL 3.0 protocols, as well as the '--insecure' flag, when executed by applications like openssl, gpg, ssh, or curl. This could indicate an adversary attempting to downgrade cryptographic protections to facilitate eavesdropping or other attacks.
Detects a potential attempt to downgrade a password manager client's encryption to a legacy, non-authenticated mode (e.g., AES-CBC). A malicious or compromised server can send a specially crafted response during login or synchronization that forces the client to use weaker cryptography. This can compromise the integrity and confidentiality of the user's vault, enabling further attacks like vault modification or padding oracles.
This rule detects attempts to downgrade NetNTLM security settings by monitoring modifications to specific registry keys related to LSA (Local Security Authority) configuration. Specifically, it looks for changes to 'LmCompatibilityLevel', 'NtlmMinClientSec', and 'RestrictSendingNTLMTraffic' within the 'SYSTEM\ControlSet\Control\Lsa' registry path. Such modifications can weaken NTLM authentication security, potentially enabling downgrade attacks where an attacker forces a less secure authentication protocol.
Detects modifications to specific registry keys related to NetNTLM authentication settings. These modifications can indicate an attempt to downgrade NetNTLM security, potentially enabling NetNTLM downgrade attacks. The rule specifically looks for changes to 'lmcompatibilitylevel', 'NtlmMinClientSec', and 'RestrictSendingNTLMTraffic' within the LSA registry path to less secure values.
Detects the exploitation of CVE-2022-37966, a security bypass and elevation of privilege vulnerability in Kerberos that allows for weak RC4-HMAC negotiation. This event indicates a Kerberos KDC error related to this vulnerability.
Detects scenarios where an attacker modifies the registry configuration in order to enable or downgrade NTLM protocol version, to later on perform relay attacks.
Detects scenarios where an attacker attempts to enable insecure guest authentication in order to access a remote storage device (NAS) in order to perform some data exfiltration or lateral movement.
KQL Query from file: External Attack Surface Monitoring KQL
KQL Query from file: DefenderXDR MITRE ATT&CK Technique Analysis
Goal: Find machines in the last N days where the SystemGuardSecurityLevel value NOW is less than it was BEFORE.
Step 1: Get a list of all security levels in the system where the level is not null.
Step 1: Get a list of all security levels in the system where the level is not null.
Expanding on DeviceEvents output with Attack Surface Reduction (ASR) rule descriptions.
The ActionType values of the ASR events already explain what rule was matched and if it was audited or blocked.
However, it could still be useful to have a more human-friendly description in the results.
Also, this query is a good example for how you could define your own lookup tables and join with them.
The events in the DeviceEvents table contain a GUID for the various ASR rules rather than a full description of the rule.
This query will create a table which has the description for each ASR rule as per https://docs.microsoft.com/windows/security/threat-protection/windows-defender-exploit-guard/enable-attack-surface-reduction.
This table is then joined to the output of a query against the DeviceEvents table and shows a summary count of the events by the newly defined description.
This query shows the ability to use joins and custom dimension tables.
See https://docs.loganalytics.io/docs/Language-Reference/Tabular-operators/join-operator for more information on the join syntax.
For more questions on this query, feel free to ping @FlyingBlueMonki on twitter or mattegen@microsoft.com via email.
First lets start by creating a table of the rule descriptions to rule guids.
The ActionType values of the ASR events already explain what rule was matched and if it was audited or blocked.
However, it could still be useful to have a more human-friendly description in the results.
Also, this query is a good example for how you could define your own lookup tables and join with them.
The events in the DeviceEvents table contain a GUID for the various ASR rules rather than a full description of the rule.
This query will create a table which has the description for each ASR rule as per https://docs.microsoft.com/windows/security/threat-protection/windows-defender-exploit-guard/enable-attack-surface-reduction.
This table is then joined to the output of a query against the DeviceEvents table and shows a summary count of the events by the newly defined description.
This query shows the ability to use joins and custom dimension tables.
See https://docs.loganalytics.io/docs/Language-Reference/Tabular-operators/join-operator for more information on the join syntax.
For more questions on this query, feel free to ping @FlyingBlueMonki on twitter or mattegen@microsoft.com via email.
First lets start by creating a table of the rule descriptions to rule guids.
Detects the usage of the "reg.exe" utility to disable PPL protection on the LSA process
Get stats on ASR audit events - count events and machines per rule.
'Identifies instances where Wazuh logged over 400 '403' Web Errors from one IP Address. To onboard Wazuh data into Sentinel please view: https://github.com/wazuh/wazuh-documentation/blob/master/source/azure/monitoring%20activity.rst'
Detects the usage of the "reg.exe" utility to disable PPL protection on the LSA process
Page 1 of 2