Malicious PDF — malware analysis report

Static analysis result for SHA-256 50bfd98905d17a55…

MALICIOUS

PDF

95.2 KB Created: 2021-08-03 10:22:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b4e459170ff8c040e21df07347ca780f SHA-1: fc3648e75358b8c1b0d5d2e5961c72f3550958e0 SHA-256: 50bfd98905d17a553eab99034d3cdcfb4f3ce554a7529e2274aea5b10ec40b50
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Numerous heuristics point to the PDF acting as a link farm, directing users to various external websites, some hosted on compromised WordPress installations. The presence of 'utm_term=attachment report format jkuat' suggests a lure related to reports or attachments, commonly used in phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://philabc.ru/uplcv?utm_term=attachment+report+format+jkuat PDF link annotation
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/ga47p4ckl73275hg96nnrjg355/43457711327.pdfIn PDF document text
    • https://alubiasdetolosa.com/files/galeria/files/nemuxebutoduwebovirako.pdfIn PDF document text
    • http://manpukuorder.com/uploads/files/lapexured.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/lasixutozuwoli.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/cdb4e5d9f56a2f2e2e65256218ac5cb4/vipogafe.pdfIn PDF document text
    • https://nslogisticservice.com/userfiles/files/pimovaluzimid.pdfIn PDF document text
    • https://maxlinder.com/admin/assets/ckfinder/userfiles/files/38741609655.pdfIn PDF document text
    • https://stayinbranson.com/ckfinder/triplebuserfiles/file/nomikupatifixagalowuku.pdfIn PDF document text
    • http://syarmarka.ru/userfiles/files/zagiku.pdfIn PDF document text
    • http://fertilityupdates.com/userfiles/files/67309199310.pdfIn PDF document text
    • http://webinaris.net/ckfinder/userfiles/publics/files/41346459669.pdfIn PDF document text
    • https://koffiewarenhuis.nl/app/webroot/files/userfiles/files/21882578036.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae3b84ee3af---gurebujimupejulateneda.pdfIn PDF document text
    • http://tunesistudio.eu/userfiles/files/napabokuwo.pdfIn PDF document text
    • http://j-club.eu/userfiles/file/kuronegadexavevuwubagit.pdfIn PDF document text
    • http://steps4cancer.org/clients/a/a7/a78c374070a178914b502abaf3db82b8/File/litadumelaxetozevoke.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b05672af709---55097285204.pdfIn PDF document text
    • https://rfcorporation.net/wp-content/plugins/super-forms/uploads/php/files/627faa00b81154a1cb9df7355c993313/50352549888.pdfIn PDF document text
    • https://lose-weight.tw/upload/files/suterezofo.pdfIn PDF document text
    • http://asdgolfclubtoscana.com/writable/public/userfiles/file/xomel.pdfIn PDF document text
    • http://b-solutions.net/userfiles/file/97767911090.pdfIn PDF document text
    • https://ooobelkom.ru/ckfinder/userfiles/files/xoxasunirivisaxi.pdfIn PDF document text
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160be3d0ec897a---60598931639.pdfIn PDF document text
    • https://forumhrdbekasi.com/webroot/userfiles/files/gavekiv.pdfIn PDF document text
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/f7bc8ab80a0fb9959845604100022261/rimawisipux.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_off00011081.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11081 10740 bytes
SHA-256: cc20f90fb071cb21c72ea7875bd32941fbfe3a34a18cb0fd811afc3fd0fc76a9
font_01_sfnt_off00012917.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12917 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014129.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14129 17260 bytes
SHA-256: 8ae680b783f3f6a2a70da5efc430895d64981f798504133fb43ab45478521911