Malicious PDF — malware analysis report

Static analysis result for SHA-256 c156771ac462c7b9…

MALICIOUS

PDF

79.2 KB Created: 2021-06-30 02:17:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: d45d6df154ee921e2eacb26b7b927bc3 SHA-1: 871cc485da534392eb537be8e46fe4531465e88e SHA-256: c156771ac462c7b958a63136520a8159002a7e3d5e1da408a76d38fcb505aa90
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains a link farm pointing to numerous distinct hosts, many of which appear to be compromised WordPress sites or disposable hosting. The primary purpose seems to be directing users to potentially malicious content hosted across these domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9933

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://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f156c42f51---68879628577.pdf In PDF document text
    • https://bloomeng.com/uploads/92063997520.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/0a2b0f7e987b5adb88cf20e52c5d8eae/53441041244.pdfIn PDF document text
    • https://opuntia.eu/wp-content/plugins/super-forms/uploads/php/files/aec1e7020363f237ff36c9b0ec9990e5/72774212476.pdfIn PDF document text
    • http://musicupclose.com/clients/f/f7/f7c291dfb329fbc33054893077acf627/File/murutekafinogatu.pdfIn PDF document text
    • http://rencontres-icare.org/userfiles/file/gosatejitogosakaruv.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/fvnv9ia5todnvemvpbeel2oj88/18030031178.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071c34b32007---75744736038.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608d9d193896e---xifadim.pdfIn PDF document text
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/ab6edcaaf627eb87fad7e46593f527fc/lojeb.pdfIn PDF document text
    • http://kripasec.com/userfiles/file/gurajudakijilek.pdfIn PDF document text
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/1e29ac552acf61d9094d32e6b32b1ea1/mekagimadov.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1607aa2fbdd860---wuvakuzuzigawesiwa.pdfIn PDF document text
    • https://chris-arnold.com/userfiles/file/10302529845.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/d69ee822d26dd4abc9275d0ea4cdbbe5/zafeluremumofodirijak.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16090b54fd7d69---86525960178.pdfIn PDF document text
    • https://pypconsultores.mx/userfiles/file/birugaxipelazekaberule.pdfIn PDF document text
    • http://africanhairbraidingsalon.com/userfiles/file/50229339938.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6ea6c96dfb---wawidimovinivowovapotopep.pdfIn PDF document text
    • http://maslatalaia.com/userfiles/file/96983978735.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce1901ed89---70748798737.pdfIn PDF document text
    • http://0965818789.com/CKEdit/upload/files/refukukelorogulugaraxid.pdfIn PDF document text
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/4m7o1dm7o1t9e064jfru8q1675/dikiru.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=the+maximum+shear+stress+theory+is+used+forPDF link annotation
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b03e4d5f33---mudurunesuze.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bd75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD75 16100 bytes
SHA-256: 505f1f16fb057e2a34e7666bb0a43a50f2e0b7bc0033e59b70183295ac12d2e9
font_01_sfnt_off0000d2ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2AD 16572 bytes
SHA-256: 1a968cb7f5f79e1dcf2c225b4866b445095ad88eab730b66156ebbdbacd8648c
font_02_sfnt_off0000fdbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDBF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off000115d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115D6 10748 bytes
SHA-256: b7838bafacae381f01e556b9c68385234086c869ebe6d6e23a03b56c18f7b8de