Malicious PDF — malware analysis report

Static analysis result for SHA-256 443735ae209e715c…

MALICIOUS

PDF

78.6 KB Created: 2021-09-02 22:58:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ab2060b8794fec9010c31e9681b004cb SHA-1: 992d6a3928f04f910eecf503ff6ed219b471783c SHA-256: 443735ae209e715c3763e7cf51703e4d79459b8bf24f0da69be358fe8ce373fc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a large number of external links, many of which point to other PDF files hosted on compromised websites. This behavior is indicative of a link farm, likely used for SEO manipulation or to distribute further malicious content. The ClamAV detection and ML classifier strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://tortugafilms.ca/adminfiles/file/65947420181.pdf In PDF document text
    • http://brbud.pl/userfiles/file/21958039973.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160d4ca06080cc---xugenoribi.pdfIn PDF document text
    • http://medical-1669.com/userfiles/files/fadiriv.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/a2125167cb6f0ed28e21768fc017ff1a/25374862622.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/tr7uvlbgh28adcfb54afdvs6m7/58563083184.pdfIn PDF document text
    • http://birnagarcollege.in/userfiles/file/wanerasopusimawerajapu.pdfIn PDF document text
    • https://www.couleurs-et-jardin.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609b6f3ce0dca---godetijuwenomideragig.pdfIn PDF document text
    • https://cornerstonelaw.eu/userfiles//file/judena.pdfIn PDF document text
    • http://winfielddeli.com/ckfinder/userfiles/files/korisixezelan.pdfIn PDF document text
    • http://ototavandosemesi.com/resimler/file/sidulumobalazun.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/79a36ecbc19a392041fbd1ffb6074ebd/49369078416.pdfIn PDF document text
    • http://keralabiblesociety.com/fck_uploads/file/93135041770.pdfIn PDF document text
    • http://castudio.eu/userfiles/files/38453667644.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b7bc3a43222---jiraparufifane.pdfIn PDF document text
    • https://avgdesign.com/userfiles/file/wixidozukusopiketo.pdfIn PDF document text
    • http://paradisoseminatrici.it/userfiles/files/38636515223.pdfIn PDF document text
    • http://ohxto.com/uploaded_files/userfiles/files/taxopimokupako.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abae8b0b7f6---zepokalugutiduzaf.pdfIn PDF document text
    • https://digireg.sk/upload/8725408011.pdfIn PDF document text
    • http://adveotec.com/img/file/gipogufasuxe.pdfIn PDF document text
    • http://presssimayeshahr.ir/pic/file/kiligikolapamezevoxe.pdfIn PDF document text
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/e653752ed171f9b4b297bbdd47a44696/45495052296.pdfIn PDF document text
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/v6pk2jd7r3864hq5l0d6lv6rnn/1805306817.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/ls2nl1ighm686oceenb5u4ub7f/3743582078.pdfIn PDF document text
    • http://prtourusa.com/FileData/ckfinder/files/20210814_7C9C140B0F2EAA8C.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160e2cb333d082---juval.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=kitchen+equipment+worksheet+pdfPDF link annotation
    • 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_off0000ce94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE94 11092 bytes
SHA-256: cb1dd18052c56de0775073583945063efa4cdc5f2c665f63481c8d63ab950bba
font_01_sfnt_off0000e813.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE813 17192 bytes
SHA-256: c5834782792e149f689d9afcb0e8ccf7ecef9fde659adc389f401d72ed5ca935
font_02_sfnt_off00011494.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11494 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1