Malicious PDF — malware analysis report

Static analysis result for SHA-256 40f80f3d79c5071c…

MALICIOUS

PDF

83.5 KB Created: 2021-09-16 03:04:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 25de63db2e1ce9392e0519870aaab4d3 SHA-1: e0bd52eb24e10073bdf12704c2d9b7427185c576 SHA-256: 40f80f3d79c5071c89a43ff10b5a46a479e3d8bb363ab3a8bad2cbae736697aa
156 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous external URIs, many pointing to compromised CMS upload storage or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The document body is unreadable, but the heuristic firings and URLs confirm the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://dolphinkorea.com/files/files/3361257463.pdf In PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/70r5pgqama4q837116iki16cu2/kuriwuganomuz.pdfIn PDF document text
    • http://yangs-ns.com/ckfinder/userfiles/files/20210908012024.pdfIn PDF document text
    • https://dreamscapes.ca/dream_scapes/userfiles/files/69069080434.pdfIn PDF document text
    • https://www.grdr.org/paidel/ckfinder/userfiles/files/15815576542.pdfIn PDF document text
    • https://arerp.kr/data/file///sidinuxuka.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140e32e1bcef---mudexivu.pdfIn PDF document text
    • http://nyett.hk/uploads/news/files/78792963663.pdfIn PDF document text
    • http://macierz-grodziec.org/files/file/96358425412.pdfIn PDF document text
    • http://www.valaisconsulting.ch/file/gidenopawabareb.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161409583920b1---rurisumup.pdfIn PDF document text
    • https://myphambambi.com/webroot/img/files/82192013298.pdfIn PDF document text
    • http://glovimex.com/uploads/ckfinder/files/81467359901.pdfIn PDF document text
    • http://strategie-online.net/catalogue_dynamique/file/junekevexibogedik.pdfIn PDF document text
    • http://americansemitruckparts.com/d/files/xedovadoji.pdfIn PDF document text
    • http://burbank.kopanramen.com/uploads/files/6250523769.pdfIn PDF document text
    • https://zakarpattya-tour.com/upload/xokidigudatuw.pdfIn PDF document text
    • https://corianderedmonton.com/ckfinder/userfiles/files/zizibef.pdfIn PDF document text
    • http://kubkao-kubpla.com/userfiles/files/noveginelame.pdfIn PDF document text
    • http://daotaoyduoc.org/wp-content/plugins/super-forms/uploads/php/files/b0b6f0f740051b118a6efcdeea0a851f/togawiputipovozi.pdfIn PDF document text
    • http://tpt.taipei/asset/uploads/files/54420570594.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/xulilavimasosebemosa.pdfIn PDF document text
    • https://mr-alian.com/upload/ckfinder/files/80443253279.pdfIn PDF document text
    • http://kezmosas.hu/files/file/47110854305.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=telecharger+service+google+play+gratuitPDF 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_off0000e297.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE297 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000faa9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAA9 17020 bytes
SHA-256: ceb433261b2000b032022a297ef50c1b5f225944b67bf1bcd426815a359604a2
font_02_sfnt_off000126ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126CE 10792 bytes
SHA-256: 0e63692eb4de74e77411fd52e642a6a259f6f8ae4843bb62800b578ed0c180d5