Malicious PDF — malware analysis report

Static analysis result for SHA-256 d167b9b38da22a99…

MALICIOUS

PDF

88.0 KB Created: 2021-07-30 09:25:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: eefaf50ca716c3e25845b03ec723ad22 SHA-1: 0c2d25b62be00b4019ecd924b75a025904bc57c2 SHA-256: d167b9b38da22a994ec7b08da7c5cbf63788c6094b3a08d09b226b3ae56daf58
156 Risk Score

Malware Insights

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

The sample is a PDF document identified as malicious by ML classifiers and ClamAV. It contains a link farm pointing to multiple PDF files hosted on compromised WordPress sites, indicating a phishing or malware distribution attempt. The document body is unreadable binary data, but the heuristics strongly suggest a malicious intent through the use of these compromised hosting sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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 http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/00ccae4bd82ad75fb5008da24f85fc00/14700136070.pdf In PDF document text
    • https://iescolumbus.org/wp-content/plugins/super-forms/uploads/php/files/fa5a2cf366d001844dcd9ad9e052737c/mebelewabogugitanapaf.pdfIn PDF document text
    • http://ucity68.com/clients/e/ea/ea220da86df44fb0ae3b7c8e8295ccc1/File/wovobogenatedirat.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/r648ib7knd9k6ouufjr0ck2oia/89534406777.pdfIn PDF document text
    • http://masterref.ru/editorfiles/file/gidogeva.pdfIn PDF document text
    • http://symbioticlifetech.org/attfile/fckimg/file///2021060784747_716151447.pdfIn PDF document text
    • http://matthewsmillsreunion.com/clients/c/c7/c7863f7b93cb17915b2a89d887155530/File/34453547372.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/160706a0594f7b---59277783656.pdfIn PDF document text
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/0991cdcfad7a9fe1aa93cf9e0bda03a7/nolumipilokevukepuletolun.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7ab7c2198---98230465888.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607f5ad848588---96807370241.pdfIn PDF document text
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/005e97fdd4656328ca89b0539837e13f/nenexowalemewiwusefura.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c7efea82ba---ruwusatorokawasil.pdfIn PDF document text
    • http://denki-shonan.com/uploadsfile/wotalojorilatagatopugefuz.pdfIn PDF document text
    • http://orikon.net/Images_upload/files/98784481857.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/42d7b1fbeef42eb623fee8bcdf70c0a3/57570891558.pdfIn PDF document text
    • https://iominneapolis.com/wp-content/plugins/super-forms/uploads/php/files/8e89b76d5162e46492280cddbb256c0f/pugoferogofomixobado.pdfIn PDF document text
    • http://z500.si/files/81329854831.pdfIn PDF document text
    • http://www.anieliasfx.com/uploads/textareas/file/79823110212.pdfIn PDF document text
    • http://polskienarty.pl/data/aktualnosci_imgs/file/podunafusi.pdfIn PDF document text
    • http://thebeautyofdesign.nl/ckfinder/userfiles/files/87317778404.pdfIn PDF document text
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/6e0ad1a0fb9c35afec14ab55064a0d12/90031818730.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f1db7840e45---bitiderolo.pdfIn PDF document text
    • http://newgatedesign.com/Images_upload/files/tikoresigifez.pdfIn PDF document text
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/5292ee65e9e5732606109624f979ef32/63149385628.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=what+is+the+function+of+information+technology+in+business+todayPDF 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_off0000f502.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF502 15964 bytes
SHA-256: 94cf36764b83a0591930cf9936d6ce911ca88e841c8dc94cf321b0d947fdb91a
font_01_sfnt_off00011e10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E10 11268 bytes
SHA-256: bf28727aff7df55aeea2d05530979bd1db475425a23679081af30e68dff97b72
font_02_sfnt_off0001382b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1382B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1