Coverage › CVE-2021-42258
CVE-2021-42258 Mapped Sigma
BQE BillQuick Web Suite SQL Injection Vulnerability
- Vendor / product
- BQE — BillQuick Web Suite
- Description (CISA)
- BQE BillQuick Web Suite contains an SQL injection vulnerability when accessing the username parameter that may allow for unauthenticated, remote code execution.
- Added to KEV
- 2021-11-03
- Due date
- 2021-11-17
- Required action
- Apply updates per vendor instructions.
- Known ransomware use
- Known
- CWE
- CWE-89
- CISA notes
- https://nvd.nist.gov/vuln/detail/CVE-2021-42258
- Elsewhere
- cve.org · NVD · CISA KEV · JSON
ATT&CK techniques · CTID Mappings Explorer, ATT&CK 16.1, KEV snapshot 2025-07-28
2 mapping objects across 2 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 |
|---|---|---|---|
| T1059 Command and Scripting Interpreter | primary impact | CVE-2021-42258 is a SQL injection vulnerability in BillQuick Web Suite that allows attackers to execute arbitrary SQL commands on the database server ref 1 · ref 2 |
live |
| T1486 Data Encrypted for Impact | secondary impact | CVE-2021-42258 is a SQL injection vulnerability in BillQuick Web Suite that allows attackers to execute arbitrary SQL commands on the database server ref 1 · ref 2 |
live |
Detection chain · ATT&CK Enterprise v19.2 detection strategies, analytics, log sources
T1059 Command and Scripting Interpreter primary impact
- DET0516 Behavioral Detection of Command and Scripting Interpreter Abuse
AN1428 WindowsDetects the execution of scripting or command interpreters (e.g., powershell.exe, cmd.exe, wscript.exe) outside expected administrative time windows or from abnormal user contexts, often followed by encoded/obfuscated arguments or secondary execution events.Tunable:
CommandLinePatternParentProcessNameTimeWindowAN1429 LinuxDetects use of shell interpreters (e.g., bash, sh, python, perl) initiated by users or processes not normally executing them, especially when chaining suspicious utilities like netcat, curl, or ssh.Tunable:InterpreterNameUserContextExecutionChainLengthAN1430 macOSDetects launch of command-line interpreters via Terminal, Automator, or hiddenosascript, especially when parent process lineage deviates from user-initiated applications.macos:unifiedloglog stream --info --predicate 'eventMessage CONTAINS "exec"'→ DC0032 Process CreationTunable:LaunchAgentNameScriptNameTerminalAppUsageAN1431 ESXiDetects use of 'esxcli system' or direct interpreter commands (e.g., busybox shell) invoked from SSH or host terminal unexpectedly.Tunable:ShellEnabledFlagSSHContextAN1432 Network DevicesIdentifies CLI interpreter access (e.g., Cisco IOS, Juniper JUNOS) viaenablemode or scripting-capable sessions used by uncommon accounts or from unknown IPs.Tunable:UserRoleDeviceType
Sigma rules tagged attack.t1059 (95)
Author: Sohan G (D4rkCiph3r)
· 2023-04-05 · logsource: product=macos category=process_creation · 0250638a-2b28-4541-86fc-ea4c558fa0c6
Detects suspicious child processes spawned from browsers. This could be a result of a potential web browser exploitation.
Author: Nasreddine Bencherchali (Nextron Systems)
· 2023-04-17 · logsource: product=windows category=process_creation · 05ebafc8-7aa2-4bcd-a269-2aec93f9e842
Detects usage of winget to add new additional download sources
Author: Victor Sergeev, oscd.community
· 2020-10-09 (modified 2024-04-23) · logsource: product=windows category=process_creation · 06b401f4-107c-4ff9-947f-9ec1e7649f1e
Detects execution of "ftp.exe" script with the "-s" or "/s" flag and any child processes ran by "ftp.exe".
Author: Nasreddine Bencherchali (Nextron Systems), E.M. Anhaus (originally from Atomic Blue Detections, Endgame), oscd.community
· 2022-06-14 (modified 2023-01-04) · logsource: product=windows category=process_creation · 0955e4e1-c281-4fb9-9ee1-5ee7b4b754d2
Detects execition of commands and binaries from the context of The program compatibility assistant (Pcalua.exe). This can be used as a LOLBIN in order to bypass application whitelisting.
Author: Swachchhanda Shrawan Poudel (Nextron Systems)
· 2025-11-25 · logsource: product=linux category=process_creation · 11bb9b26-4179-4a06-afcb-1ec31fce1627
Detects potential Shai-Hulud malware indicators based on specific command line arguments associated with its execution.
Author: Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems)
· 2022-02-08 (modified 2026-02-17) · logsource: product=windows category=process_creation · 1228c958-e64e-4e71-92ad-7d429f4138ba
Detects suspicious script execution from suspicious directories or folders accessible by environment variables that may indicate malware activity.
Script interpreters (cscript, wscript, mshta, powershell) executing from folders like Temp, Public, or user profile directories may suggest attempts to evade detection or execute malicious scripts.
Author: Josh Nickels, Marius Rothenbücher
· 2024-09-06 · logsource: product=windows category=dns_query · 12310575-e8b1-475c-a976-57ed540b349c
Detects unusual domain resolutions originating from CScript/WScript that can identify malicious javascript files executing in an environment, often as a result from a phishing or watering hole attack.
Author: Florian Roth (Nextron Systems)
· 2021-11-20 (modified 2023-03-29) · logsource: product=windows category=file_event · 1277f594-a7d1-4f28-a2d3-73af5cbeab43
Detects Windows shells and scripting applications that write files to suspicious folders
Author: frack113, Tim Shelton (update fp)
· 2022-12-05 (modified 2025-03-06) · logsource: product=windows category=process_creation · 178e615d-e666-498b-9630-9ed363038101
Detects when a shell program such as the Windows command prompt or PowerShell is launched with system privileges from a uncommon parent location.
Author: Micah Babinski
· 2023-10-15 · logsource: product=windows category=file_event · 1a433e1d-03d2-47a6-8063-ece992cf4e73
Detects the usage of curl.exe, KeyScramblerLogon, or other non-standard/suspicious processes used to create Autoit3.exe.
This activity has been associated with DarkGate malware, which uses Autoit3.exe to execute shellcode that performs
process injection and connects to the DarkGate command-and-control server. Curl, KeyScramblerLogon, and these other
processes consitute non-standard and suspicious ways to retrieve the Autoit3 executable.
Author: Andreas Braathen (mnemonic.io)
· 2023-11-14 · logsource: product=windows category=process_creation · 1ddaa9a4-eb0b-4398-a9fe-7b018f9e23db
Detects exploitation attempt of CVE-2023-22518 (Confluence Data Center / Confluence Server), where an attacker can exploit vulnerable endpoints to e.g. create admin accounts and execute arbitrary commands.
Author: Nasreddine Bencherchali (Nextron Systems)
· 2023-01-02 · logsource: product=windows category=process_creation · 20a5ffa1-3848-4584-b6f8-c7c7fd9f69c8
Detects execution of ruby using the "-e" flag. This is could be used as a way to launch a reverse shell or execute live ruby code.
Author: Tim Rauch (rule), Elastic (idea)
· 2022-10-17 · logsource: product=macos category=process_creation · 234dc5df-40b5-49d1-bf53-0d44ce778eca
Detects when a built-in utility is used to decode and decrypt a payload after a macOS disk image (DMG) is executed. Malware authors may attempt to evade detection and trick users into executing malicious code by encoding and encrypting their payload and placing it in a disk image file. This behavior is consistent with adware or malware families such as Bundlore and Shlayer.
Author: Nasreddine Bencherchali (Nextron Systems)
· 2023-06-14 · logsource: product=windows category=process_creation · 236d8e89-ed95-4789-a982-36f4643738ba
Detects execution of the "VMwareToolBoxCmd.exe" with the "script" and "set" flag to setup a specific script that's located in a potentially suspicious location to run for a specific VM state
Author: Nasreddine Bencherchali (Nextron Systems), X__Junior (Nextron Systems)
· 2024-01-11 · logsource: product=windows category=process_creation · 2433a154-bb3d-42e4-86c3-a26bdac91c45
Detects the execution of a renamed "PingCastle" binary based on the PE metadata fields.
All 95 rules on the technique page →
T1486 Data Encrypted for Impact secondary impact
- DET0215 Detection of Multi-Platform File Encryption for Impact
AN0602 WindowsHigh-frequency file write operations using uncommon extensions, followed by ransom note creation, registry tampering, or shadow copy deletion. Often uses CLI tools like vssadmin, wbadmin, cipher, or PowerShell.Tunable:
FileExtensionTargetFolderTimeWindowCommandLineAN0603 LinuxEncryption via custom or open-source tools (e.g., openssl, gpg, aescrypt) recursively targeting user or system directories. Also includes overwrite of existing data and ransom note drops.Tunable:FilenamePatternSyscallBurstRateDirectoryTargetedAN0604 macOSUserland or kernel-level ransomware encrypting user files (Documents, Desktop) usingsrm,gpg, or compiled payloads. Often correlated with ransom note creation in multiple directories.macos:unifiedlogfile encrypted|new file with .encrypted extension|disk write burst→ DC0061 File ModificationTunable:ExtensionPatternVolumeTargetedAN0605 ESXiRansomware encrypts .vmdk, .vmx, .log, or VM config files in VMFS datastores. May rename to .locked or delete/overwrite with encrypted versions. Often correlates with shell commands run throughdcui, SSH, or vSphere.Tunable:FileTypeUserContextAN0606 IaaSEncryption of cloud storage objects (e.g., S3 buckets) via Server-Side Encryption (SSE-C) or by replacing objects with encrypted variants. May include API patterns like PutObject with SSE-C headers.Tunable:SSEHeaderAffectedBucketUserAgent
Sigma rules tagged attack.t1486 (16)
Author: frack113
· 2021-11-15 (modified 2022-09-09) · logsource: product=windows category=process_creation · 0e0255bf-2548-47b8-9582-c0955c9283f5
Detects suspicious addition to BitLocker related registry keys via the reg.exe utility
Author: toopricey
· 2025-10-18 · logsource: product=aws service=cloudtrail · 1279262f-1464-422f-ac0d-5b545320c526
Detects the import or deletion of key material in AWS KMS, which can be used as part of ransomware attacks. This activity is uncommon and provides a high certainty signal.
Author: Sittikorn S
· 2021-06-29 (modified 2021-08-20) · logsource: product=aws service=cloudtrail · 16124c2d-e40b-4fcc-8f2c-5ab7870a2223
Identifies disabling of default Amazon Elastic Block Store (EBS) encryption in the current region.
Disabling default encryption does not change the encryption status of your existing volumes.
Author: Saiprashanth Pulisetti ( @Prashanthblogs)
· 2025-08-08 · logsource: product=windows category=file_event · 2c76a22b-702d-48fd-8fa9-e41e2fe203b3
Detects the creation of files with the ".funksec" extension, which is appended to encrypted files by the FunkLocker ransomware.
Author: Luc Génaux
· 2023-11-28 (modified 2026-07-28) · logsource: product=windows category=image_load · 3669afd2-9891-4534-a626-e5cf03810a61
Detects the load of RstrtMgr DLL (Restart Manager) by an uncommon process.
This library has been used during ransomware campaigns to kill processes that would prevent file encryption by locking them (e.g. Conti ransomware, Cactus ransomware). It has also recently been seen used by the BiBi wiper for Windows.
It could also be used for anti-analysis purposes by shut downing specific processes.
Author: Florian Roth (Nextron Systems), Tom U. @c_APT_ure (collection), oscd.community, Jonhnathan Ribeiro
· 2019-01-16 (modified 2025-10-18) · logsource: product=windows category=process_creation · 41d40bff-377a-43e2-8e1b-2e543069e079
Detects WannaCry ransomware activity
Author: Florian Roth (Nextron Systems), Arnim Rupp
· 2022-05-12 (modified 2026-06-15) · logsource: category=antivirus · 4c6ca276-d4d0-4a8c-9e4c-d69832f8671f
Detects a highly relevant Antivirus alert that reports ransomware.
This event must not be ignored just because the AV has blocked the malware but investigate, how it came there in the first place.
Author: frack113
· 2021-10-12 (modified 2023-02-13) · logsource: product=windows category=process_creation · 689308fc-cfba-4f72-9897-796c1dc61487
Detects a specific command used by the Conti ransomware group
Author: Vasiliy Burov, oscd.community
· 2020-10-18 (modified 2023-02-03) · logsource: product=windows category=process_creation · 74db3488-fd28-480a-95aa-b7af626de068
Detects LockerGoga ransomware activity via specific command line.
Author: frack113, Nasreddine Bencherchali (Nextron Systems)
· 2023-08-06 (modified 2023-11-10) · logsource: product=windows category=process_creation · 77df53a5-1d78-4f32-bc5a-0e7465bd8f41
Detects the execution of "gpg.exe" from uncommon location. Often used by ransomware and loaders to decrypt/encrypt data.
Author: Luc Génaux
· 2023-11-28 · logsource: product=windows category=image_load · b48492dc-c5ef-4572-8dff-32bc241c15c8
Detects the load of RstrtMgr DLL (Restart Manager) by a suspicious process.
This library has been used during ransomware campaigns to kill processes that would prevent file encryption by locking them (e.g. Conti ransomware, Cactus ransomware). It has also recently been seen used by the BiBi wiper for Windows.
It could also be used for anti-analysis purposes by shut downing specific processes.
Author: austinsonger
· 2021-08-19 (modified 2022-10-09) · logsource: product=m365 service=threat_management · bd132164-884a-48f1-aa2d-c6d646b04c69
Detects when a Microsoft Cloud App Security reported when a user uploads files to the cloud that might be infected with ransomware.
Author: frack113
· 2021-12-26 (modified 2026-01-09) · logsource: product=windows category=file_event · caf02a0a-1e1c-4552-9b48-5e070bd88d11
Detects creation of .txt files in user desktop folders via cmd.exe. This behavior may indicate ransomware deploying ransom notes, but can also occur during legitimate administrative tasks.
Analysts should investigate for suspicious filenames (e.g., "RANSOM", "DECRYPT", "READ_ME"), bulk file creation patterns, or concurrent encryption activity to determine if this is part of a ransomware attack.
Author: frack113
· 2022-07-16 (modified 2023-11-11) · logsource: product=windows category=file_rename · e3f673b3-65d1-4d80-9146-466f8b63fa99
Detects file renames where the target filename uses an uncommon double extension. Could indicate potential ransomware activity renaming files and adding a custom extension to the encrypted files, such as ".jpg.crypted", ".docx.locky", etc.
Author: Nasreddine Bencherchali (Nextron Systems), frack113
· 2023-08-09 · logsource: product=windows category=process_creation · ec0722a3-eb5c-4a56-8ab2-bf6f20708592
Detects the execution of a renamed "gpg.exe". Often used by ransomware and loaders to decrypt/encrypt data.