Malicious PDF — malware analysis report

Static analysis result for SHA-256 9603f8433dd7d3d2…

MALICIOUS

PDF

87.9 KB Created: 2021-08-14 03:59:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-23
MD5: b10cd8676fb6b31c183c0c68ecd9155f SHA-1: e4f721c0afd967b085afaf3822fd06e4bcc8b43f SHA-256: 9603f8433dd7d3d283438424d598a4f34d742eba39d3e4d6cf8b3b350173a7ef
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document was flagged as malicious by 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 0.9991

Heuristics 5

  • 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=printable+brush+calligraphy+practice+sheets+pdf PDF link annotation
    • http://schokofontaenen.de/idata/safufumumafasajugux.pdfIn PDF document text
    • https://nakipoglugroup.com/upload/ckfinder/files/fenav.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b429d1c871---26205041239.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/b1467d981cd2170b12d884824382cd6c/moninajowa.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/91da8f7263e72acd62ce6590ce5db817/lewemugububuk.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160aa976e98989---diwikerapuraduwukafobawe.pdfIn PDF document text
    • https://basealimentare.it/webroot/files/fck_uploads/File/73600619117.pdfIn PDF document text
    • https://thaiwoodengames.com/files/upload/files/nudipilizutavuwalegolor.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/42650482e2e57c94dc8ff9df85672f26/fawofudolinajurit.pdfIn PDF document text
    • https://eandjfamilyhealthcenter.com/wp-content/plugins/super-forms/uploads/php/files/d200e2b7a23e06551526273c9fa16eaa/50161807451.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b772e8eb74---daruzamima.pdfIn PDF document text
    • http://cloverdiamond.com/file/11673743217.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160df48e029c20---62635409160.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1607cb94878d2f---zajowelegub.pdfIn PDF document text
    • http://homespakistan.net/magzine/uploadfiles/file/mitosa.pdfIn PDF document text
    • http://kehlux.lu/userfiles/files/dotego.pdfIn PDF document text
    • http://brenno-tojestto.pl/userfiles/file/49157971638.pdfIn PDF document text
    • http://perfectionistpaintingnj.com/ckfinder/userfiles/files/65501651503.pdfIn PDF document text
    • http://fueandhair.com/userfiles/files/25386238670.pdfIn PDF document text
    • http://topas.lt/userfiles/file/81392361506.pdfIn PDF document text
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/s0kn6b21oe1na601ldvno6d443/sabozoradijumasazekisax.pdfIn PDF document text
    • http://cn-daomeng.com/upload/userfiles/files/a6dc9e8c19d9ad2fbdfca8b809602fcb.pdfIn PDF document text
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbd44c810b---74579703974.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_off0000f0b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0B8 17904 bytes
SHA-256: 03f1dd96ec394cb2a744bd03638ec853d77137b6edee2334b29613921637d14a
font_01_sfnt_off00011fae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FAE 11136 bytes
SHA-256: 1c8e34747daac3b422153d8b16cc6780fcb28c33d3192f7e52b6d2f2e79f94f8
font_02_sfnt_off00013937.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13937 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1