diff --git a/rules/windows/file/file_event/file_event_win_office_outlook_rdp_file_creation.yml b/deprecated/windows/file_event_win_office_outlook_rdp_file_creation.yml similarity index 97% rename from rules/windows/file/file_event/file_event_win_office_outlook_rdp_file_creation.yml rename to deprecated/windows/file_event_win_office_outlook_rdp_file_creation.yml index 046310174..fabcab63a 100644 --- a/rules/windows/file/file_event/file_event_win_office_outlook_rdp_file_creation.yml +++ b/deprecated/windows/file_event_win_office_outlook_rdp_file_creation.yml @@ -3,7 +3,7 @@ id: f748c45a-f8d3-4e6f-b617-fe176f695b8f related: - id: fccfb43e-09a7-4bd2-8b37-a5a7df33386d type: derived -status: experimental +status: deprecated description: | Detects the creation of files with the ".rdp" extensions in the temporary directory that Outlook uses when opening attachments. This can be used to detect spear-phishing campaigns that use RDP files as attachments. @@ -13,7 +13,7 @@ references: - https://www.linkedin.com/feed/update/urn:li:ugcPost:7257437202706493443?commentUrn=urn%3Ali%3Acomment%3A%28ugcPost%3A7257437202706493443%2C7257522819985543168%29&dashCommentUrn=urn%3Ali%3Afsd_comment%3A%287257522819985543168%2Curn%3Ali%3AugcPost%3A7257437202706493443%29 author: Florian Roth date: 2024-11-01 -modified: 2024-11-03 +modified: 2025-07-22 tags: - attack.defense-evasion logsource: diff --git a/rules/windows/file/file_event/file_event_win_office_outlook_susp_file_creation_in_temp_dir.yml b/rules/windows/file/file_event/file_event_win_office_outlook_susp_file_creation_in_temp_dir.yml new file mode 100644 index 000000000..3aaabb822 --- /dev/null +++ b/rules/windows/file/file_event/file_event_win_office_outlook_susp_file_creation_in_temp_dir.yml @@ -0,0 +1,43 @@ +title: Suspicious File Created in Outlook Temporary Directory +id: fabb0e80-030c-4e3e-a104-d09676991ac3 +related: + - id: f748c45a-f8d3-4e6f-b617-fe176f695b8f + type: obsolete +status: experimental +description: | + Detects the creation of files with suspicious file extensions in the temporary directory that Outlook uses when opening attachments. + This can be used to detect spear-phishing campaigns that use suspicious files as attachments, which may contain malicious code. +references: + - https://vipre.com/blog/svg-phishing-attacks-the-new-trick-in-the-cybercriminals-playbook/ + - https://thecyberexpress.com/rogue-rdp-files-used-in-ukraine-cyberattacks/ + - https://www.microsoft.com/en-us/security/blog/2024/10/29/midnight-blizzard-conducts-large-scale-spear-phishing-campaign-using-rdp-files/ +author: Florian Roth (Nextron Systems), Swachchhanda Shrawan Poudel (Nextron Systems) +date: 2025-07-22 +tags: + - attack.initial-access + - attack.t1566.001 +logsource: + product: windows + category: file_event +detection: + selection_extension: + TargetFilename|endswith: + - '.cpl' + - '.hta' + - '.iso' + - '.rdp' + - '.svg' + - '.vba' + - '.vbe' + - '.vbs' + selection_location: + - TargetFilename|contains: + - '\AppData\Local\Packages\Microsoft.Outlook_' + - '\AppData\Local\Microsoft\Olk\Attachments\' + - TargetFilename|contains|all: + - '\AppData\Local\Microsoft\Windows\' + - '\Content.Outlook\' + condition: all of selection_* +falsepositives: + - Opening of headers or footers in email signatures that include SVG images or legitimate SVG attachments +level: high diff --git a/rules/windows/file/file_event/file_event_win_susp_double_extension.yml b/rules/windows/file/file_event/file_event_win_susp_double_extension.yml index c9a07092e..3bd6f6098 100644 --- a/rules/windows/file/file_event/file_event_win_susp_double_extension.yml +++ b/rules/windows/file/file_event/file_event_win_susp_double_extension.yml @@ -14,9 +14,10 @@ references: - https://twitter.com/malwrhunterteam/status/1235135745611960321 - https://twitter.com/luc4m/status/1073181154126254080 - https://cloud.google.com/blog/topics/threat-intelligence/cybercriminals-weaponize-fake-ai-websites + - https://vipre.com/blog/svg-phishing-attacks-the-new-trick-in-the-cybercriminals-playbook/ author: Nasreddine Bencherchali (Nextron Systems), frack113 date: 2022-06-19 -modified: 2025-05-30 +modified: 2025-07-22 tags: - attack.defense-evasion - attack.t1036.007 @@ -29,6 +30,7 @@ detection: - '.exe' - '.iso' - '.rar' + - '.svg' - '.zip' # - '.lnk' # legitimate links can happen just anywhere TargetFilename|contains: @@ -43,7 +45,9 @@ detection: - '.png.' - '.ppt.' - '.pptx.' + - '.rtf.' - '.svg.' + - '.txt.' - '.xls.' - '.xlsx.' selection_exe: