Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9cafd1c55249b19…

MALICIOUS

PDF

82.1 KB Created: 2021-09-11 22:56:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 0a6c658ec984ee875bbfe7ef57e4c8ec SHA-1: 3446a1ff51a6e322d212af69269975fd879ec4d9 SHA-256: b9cafd1c55249b19d34ae3fbaea49836fa88ac77951b7904eddd87003ec468ef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://pixomot.ru/uplcv?utm_term=how+to+save+a+recorded+audio+file+in+android PDF link annotation
    • http://rfinshaat.az/userfiles/file/55268000500.pdfIn PDF document text
    • https://dgssu.com/upfolder/e/files/20210906174656.pdfIn PDF document text
    • http://gd-weimi.com/upfolder/e/files/20210905112648.pdfIn PDF document text
    • http://4rrecycle.com/files/file/51930355979.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f36c5df480---49757477126.pdfIn PDF document text
    • https://cvsc.co/userfiles/file/nineg.pdfIn PDF document text
    • http://bangdientunhk.com/upload/files/63834298397.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136e72b0c160---49087940410.pdfIn PDF document text
    • https://fgcrubochi.com.ng/ckfinder/userfiles/files/80995061566.pdfIn PDF document text
    • http://denetimmusavirlik.com/userfiles/file/16208971031.pdfIn PDF document text
    • http://www.annaleehuber.com/content_files/file/68289437492.pdfIn PDF document text
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613241119cb20---mogazolazovarofo.pdfIn PDF document text
    • http://www.web-globus.de/ckfinder/userfiles/files/87518850321.pdfIn PDF document text
    • http://kyanite.tv/userfiles/file/tasagenagifesit.pdfIn PDF document text
    • http://thanglong.vn-greenenergy.com/ckfinder/userfiles/files/mazegidabufabonisima.pdfIn PDF document text
    • http://thamdinhgiadaiquang.com/img/files/87731567476.pdfIn PDF document text
    • http://www.maderas-navarro.com/ckfinder/userfiles/files/domanim.pdfIn PDF document text
    • https://sunsoftinfoway.net/ckfinder/userfiles/files/62108609551.pdfIn PDF document text
    • https://reha.bg/content/upload/file/17213352226.pdfIn PDF document text
    • http://korvet-sp.ru/userfiles/file/puwiwuborude.pdfIn PDF document text
    • http://dorinhawear.com/admin/fckeditor/editor/filemanager/connectors/php/fckeditor/editor/filemanager/connectors/php/userfiles/file/38531180452.pdfIn PDF document text
    • http://www.wm-meyer.de/meyer/admin/editor/ckfinder/userfiles/files/fupewabuxekikibewovumomu.pdfIn PDF document text
    • http://theffirm.com/userfiles/file/pokazaduloterugufinedu.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dcec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCEC 10712 bytes
SHA-256: f91b81813895a9127c362311ce8fbdc0ed76c4d248073edbb76d736bf4bc773d
font_01_sfnt_off0000f5a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5A4 17208 bytes
SHA-256: ec2ca3daf8f24410545424fc9b26ad1f976201c05bb35fdeee8ba4e8dbc73804
font_02_sfnt_off00012249.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12249 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1