Malicious PDF — malware analysis report

Static analysis result for SHA-256 3ecdc28e7449841c…

MALICIOUS

PDF

100.1 KB Created: 2021-09-15 17:18:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 5d335a410e4cf9931ca47e98e1a73fc5 SHA-1: ee3dd2fb083e66eb6bd6652ecdbf706497986617 SHA-256: 3ecdc28e7449841cf30b38d29ef6a695ad654b48612166824e79b1ec6f4d124f
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous embedded links, many pointing to disposable domains, which is characteristic of phishing or malware distribution campaigns. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to trick users into downloading further malicious content. No scripts were extracted, but the PDF structure itself facilitates the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://spbmedax.ru/sites/default/files/uploads/kapisuluravuweruka.pdf In PDF document text
    • https://www.poolsrus.com.au/application/third_party/ckfinder/userfiles/files/fesilewozuzu.pdfIn PDF document text
    • http://studiomedicoveterinariobellucci.eu/userfiles/files/99281937645.pdfIn PDF document text
    • http://eichler-kammerer.de/39849979843.pdfIn PDF document text
    • https://manhremhoangvan.vn/wp-content/uploads/files/21426574424.pdfIn PDF document text
    • https://beautydent.hu/editor_up/45650566584.pdfIn PDF document text
    • http://www.nomorcantikjoss.com/file/4439585718.pdfIn PDF document text
    • http://dunakeszi.varosom.hu/userfiles/files/46875627750.pdfIn PDF document text
    • http://tumakuruvoice.com/tumkurvoice/ckeditor/ckfinder/userfiles/files/bibex.pdfIn PDF document text
    • https://arvikabc.com/images/uploadedimages/file/93463284064.pdfIn PDF document text
    • http://www.huescalamagiaenfotos.com/userfiles/files/10850481204.pdfIn PDF document text
    • http://sherwoodonionfestival.com/ckfinder/userfiles/files/61444730070.pdfIn PDF document text
    • https://www.hs-hofgastein.salzburg.at/ckfinder/userfiles/files/804342386.pdfIn PDF document text
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/97190925465b5e095c135222f0cbb623/45125549951.pdfIn PDF document text
    • http://shtaket46.ru/page_edit/_samples/userfiles/files/bunomizupis.pdfIn PDF document text
    • https://www.mediawerf.nl/bundles/store24backoffice/ckfinder/userfiles/files/jepobipisefafajizuwigom.pdfIn PDF document text
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/l8c7tcuiorsfipmjdiiernfjfo/gizokimavupumozufunexivi.pdfIn PDF document text
    • http://esistore.be/userfiles/file/28829680815.pdfIn PDF document text
    • http://verduciautodemolizioni.it/userfiles/file/lamiwom.pdfIn PDF document text
    • https://www.supremecaravans.com.au/application/third_party/ckfinder/userfiles/files/43058158226.pdfIn PDF document text
    • https://fleuriste79.fr/ckfinder/userfiles/files/22041364919.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=android+emulator+change+locationPDF 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_off000120b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120B1 10728 bytes
SHA-256: 2a1d86c5d44ab9b142da9133aa4b602c9882bfcd49129e26517be1395fc21110
font_01_sfnt_off000138f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138F2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015104.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15104 18912 bytes
SHA-256: 19ea6b3138b916daa12fcc9fc9b0678af3642b71f23ee603b7b38e4f139e83d8