Malicious PDF — malware analysis report

Static analysis result for SHA-256 76729c8becb21c64…

MALICIOUS

PDF

70.8 KB Created: 2021-09-24 23:37:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 65b9ab2065160f656f4636dac6960e2c SHA-1: 5edd195dd8734855d356e96306ad5470f69678e9 SHA-256: 76729c8becb21c648df0b213171903626f4f8a9888a936be621b0a247de061bd
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, containing numerous links to other PDF files hosted on various domains. The primary purpose appears to be SEO manipulation or distributing further malicious content through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9893

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://sanipacific.com/attachment/file/11504175463.pdf In PDF document text
    • http://aerotechgroup.ru/img/outer/files/6585464755.pdfIn PDF document text
    • http://imosa.asia/uploads/files/202109170151164759.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16139564828e57---bomedunafonan.pdfIn PDF document text
    • https://linhngapt.vn/upload/files/6319248355.pdfIn PDF document text
    • http://stphilomenaonline.org/userfiles/file/57699509455.pdfIn PDF document text
    • https://surupaceanu.ro/ckfinder/userfiles/files/kokizodamosipozax.pdfIn PDF document text
    • http://eot.mn/uploads/userfiles/files/fugamuru.pdfIn PDF document text
    • https://sikdercollegeofpharmacy.com/scp/ckfinder/uploads/userfiles/files/buvewejibuvajeriwogidi.pdfIn PDF document text
    • http://borneneskontor-landsforening.dk/userfiles/file/tagakokos.pdfIn PDF document text
    • https://euinsuti.uniluxgym.ro/app/webroot/files/userfiles/files/tidagalujujamudupad.pdfIn PDF document text
    • https://intersat.lv/files/file/xunajamituk.pdfIn PDF document text
    • http://tion.hu/upload/file/wadolegovukiz.pdfIn PDF document text
    • http://dioceseofniranam.org/userfiles/file/geramuji.pdfIn PDF document text
    • https://twinscooking.nl/twins/userfiles/file/93490926936.pdfIn PDF document text
    • https://loffoxfitness.mvwebsolution.com/userfiles/files/forute.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/25be66383ca5fb056b9c0f4095153bea/bedinawuwesoxoroside.pdfIn PDF document text
    • https://ezastupitelstvo.sk/editor_uploads/system/files/17349779798.pdfIn PDF document text
    • https://xn----8sbcehyodmtf1czh.xn--p1ai/userfiles/file/3298948727.pdfIn PDF document text
    • http://electronicaindex.nl/images/uploads/68071170284.pdfIn PDF document text
    • http://abwingsde.com/uploads/files/89317909212.pdfIn PDF document text
    • http://medizator.ru/ckfinder/userfiles/files/vipazifufasujedagosi.pdfIn PDF document text
    • http://acmemask.com/upfiles/editor/files/daxonodurixagozud.pdfIn PDF document text
    • http://lonniestireandauto.com/nbloom/fckuploads/file/57239849116.pdfIn PDF document text
    • http://ymmicro.com/files/files/19555610501.pdfIn PDF document text
    • http://yournamebadges.com/withyourdog/cms_uploads/file/sukamisupufepotozejanidog.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=spider+man+2+full+movie+in+tamilPDF 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_off0000b30c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB30C 16216 bytes
SHA-256: 97a4c38e8f1e52aa5611a066e96204d81494756c016b9e4f4c536bdc75547791
font_01_sfnt_off0000dc66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC66 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f47d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF47D 10852 bytes
SHA-256: 7fc412bd9492caa4a33d26bb31e23b0ecfa0d05cc5f3a10df636eb67d01ce394