Malicious PDF — malware analysis report

Static analysis result for SHA-256 1559554df9019b55…

MALICIOUS

PDF

84.1 KB Created: 2021-09-23 22:15:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 34f732a4155c6f0959c6d0f9bbc9a968 SHA-1: 2e8a6d68a77c28c4c75957a82c3b2500e3bef5cd SHA-256: 1559554df9019b5580775b113651b35382d7b5d2fb5300548a668e411d8ba91b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. Heuristics reveal it contains a link farm pointing to compromised CMS uploads and disposable hosting, likely to redirect users to phishing sites. No scripts were extracted, but the PDF structure itself facilitates the attack by hosting these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://allytemp.ru/uplcv?utm_term=wps+connect+y%C3%BCkle PDF link annotation
    • http://minhledtran.com/luutru/files/74777277429.pdfIn PDF document text
    • https://maintogelonline2.bet/contents/files/7379117431.pdfIn PDF document text
    • http://gostinica-domodedovo.ru/files/soletemagerifa.pdfIn PDF document text
    • https://tebra.si/userfiles/file/mapurim.pdfIn PDF document text
    • https://lesura.net/userfiles/file/dobokelafepoxejipixemi.pdfIn PDF document text
    • https://hogozaty.com/ckfinder/userfiles/files/26094819966.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147dbda66d5a---wojubikiburanupe.pdfIn PDF document text
    • https://swapnauraan.com/ckfinder/userfiles/files/wafajazomatuzogizupebu.pdfIn PDF document text
    • http://poexali.org/static/image/_u/system/files/81388476769.pdfIn PDF document text
    • https://texasbordervolunteers.org/userfiles/file/76168967794.pdfIn PDF document text
    • https://growyourmoney.in/userfiles/files/bivovubekisutir.pdfIn PDF document text
    • http://emailreceptionist.net/userfiles/file/nisovavonam.pdfIn PDF document text
    • http://ibookingkr.com/FileData/ckfinder/files/20210913_9AF491040F5776A9.pdfIn PDF document text
    • http://mdtrend.hu/files/file/11006235786.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///4632420935.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/c73ivt3hvqpk6q7tggodfn0ol7/vebabofoleropujaranu.pdfIn PDF document text
    • http://aftp.bg/userfiles/file/lenuzunemifidip.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/75420f2f4264402b217f25d7a3288a3f/begoxexevubojubuvadukovas.pdfIn PDF document text
    • http://xn--b1adbbbaeqjtsflbfms0e.xn--p1ai/pict/file/tixisesipadomirimijoregak.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/713b4b582a1273ad32257d32321e0606/77188448329.pdfIn PDF document text
    • http://s4l.vn/storage/ckfinder/files/jukarozetagogopadar.pdfIn PDF document text
    • http://intelekt.biz/uploads/pages/files/64599711774.pdfIn PDF document text
    • http://a-swiss.com/upload/userfiles/file/neluzekonuxafezifub.pdfIn PDF document text
    • http://agriturismolionsfarm.it/userfiles/files/8058710008.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_off0000dd8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD8D 20052 bytes
SHA-256: a0146e986503fc05deb3b57d6e2a153ec09868160f7ee95159c8b0b4ed9dcacc
font_01_sfnt_off000111ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012a16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A16 10404 bytes
SHA-256: 76c393951b7c24559f1e3d3d5ea2bfe3442f2a0f430ac7de758c249e045a3b00