Malicious PDF — malware analysis report

Static analysis result for SHA-256 847031a70fef3278…

MALICIOUS

PDF

77.9 KB Created: 2021-08-21 09:10:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 64e798a37dfbfdcab75e4c59f1214d79 SHA-1: d7ad09daeb55419753390d961ff690e93b14fecf SHA-256: 847031a70fef3278c37f114b2413a476e2ccb947cdbf96ab429a9ddf6878c393
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to multiple compromised WordPress sites, which in turn host other PDF files. This structure suggests a multi-stage attack, likely for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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 http://www.pilonidalsinus.gen.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607a27ce29ddb---nujutajivi.pdf In PDF document text
    • https://inverpalmas.com/aym_image/files/gamojog.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/950tvh4mbel0h5a22fj7c6cko4/96046561167.pdfIn PDF document text
    • http://helloslow.com/data/userfiles/files/jefubo.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/16075749346100---81031810567.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/d713200ec1d694d37cbf65e6f231a334/nemubesinej.pdfIn PDF document text
    • http://ambvetsanprospero.eu/userfiles/files/borizokofasib.pdfIn PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/l1ib83uh1cs2kjp9uds02spi37/nepasoligotodomo.pdfIn PDF document text
    • http://thedewakohchang.com/image/upload/File/6652057614.pdfIn PDF document text
    • http://bigcool.net/webroot/img/files/47794780098.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/1609cfcc9d4e03---76696269323.pdfIn PDF document text
    • https://alrukn.co/userfiles/files/lovokurinirilewivak.pdfIn PDF document text
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/tqtn0hvkejeqatodmlucl8skk1/36134023593.pdfIn PDF document text
    • https://ckmandarin.com/uploads/72003398407.pdfIn PDF document text
    • http://nano-vip.com/ckfinder/userfiles/files/mizimugoxigakokusosi.pdfIn PDF document text
    • http://marketypik.pl/zdjecia/fck/file/55531945768.pdfIn PDF document text
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afd6b823d42---pojizag.pdfIn PDF document text
    • http://asztalosweb.hu/userfiles/file/39926920185.pdfIn PDF document text
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/481f67420ad796173062f495df6b1e08/kozesavegujurupi.pdfIn PDF document text
    • http://biosurfest.com/userfiles/files/29297130302.pdfIn PDF document text
    • http://tcurryproperties.com/konadnew/userfiles/file/nurezapipikumugiropebape.pdfIn PDF document text
    • http://alexandersorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fikejidonutu.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/16119409dd360f---wojizirajoruzetite.pdfIn PDF document text
    • http://bmhs1963.com/clients/7/72/7286fd37811b7a5dece6e69924e4d5ab/File/54222385841.pdfIn PDF document text
    • http://mountcalvary76.com/clients/9/90/9062e1c9f2360b2cedac6e2854879500/File/votizitufi.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/cbfeaada0dfa4a976f0b76304e29430a/kaleduxojizumo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=satta+king+gali+disawar+ghaziabad+ki+listPDF 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_off0000ce58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE58 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e66a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE66A 16308 bytes
SHA-256: 5467b50b2765e27834c3063c3f259b975e417ad1b9912f8efbdb35227f10b7f5
font_02_sfnt_off000110a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110A8 10728 bytes
SHA-256: 326ef750614fbde043980265d59c66919b3c0305417ee7fc623a1691b4592299