Malicious PDF — malware analysis report

Static analysis result for SHA-256 9bf23a1bd6dda211…

MALICIOUS

PDF

70.3 KB Created: 2021-09-11 04:11:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-01
MD5: 5a4df5e08748f66f12dcbbc4c02ff137 SHA-1: 4c490f922884aab376e47a5fd7c67ab62c276ba1 SHA-256: 9bf23a1bd6dda2118e7b78a280d36e06bf0be6322115f80e586ac3a909a5d184
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://garglob.ru/uplcv?utm_term=realtor+referral+letter PDF link annotation
    • http://live-lessons.net/lcj/web/uploads/assets/file/velosebilenesabamib.pdfIn PDF document text
    • http://farmaciafici.com/userfiles/files/88892654768.pdfIn PDF document text
    • https://deltarealestate-eg.com/userfiles/file/57747629517.pdfIn PDF document text
    • https://safarekhoob.ir/basefile/safarekhoobir/files/kimubisi.pdfIn PDF document text
    • https://beyondpins.com/calisma2/files/uploads/farixefuwiriselep.pdfIn PDF document text
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/4aa41d779ec1fc243932f55350a1ca2a/48680103639.pdfIn PDF document text
    • https://telliogluhukuk.com/userfiles/file/nasit.pdfIn PDF document text
    • https://inunekocp.jp/mailmagazine/upload/files/naketiji.pdfIn PDF document text
    • https://www.htlexpress.com/ckfinder/userfiles/files/65916875526.pdfIn PDF document text
    • http://ekopaczka.pl/imgbrama/files/belagepozugebatosibigeka.pdfIn PDF document text
    • http://charolais-hessen.de/write/userfiles/file/60072158029.pdfIn PDF document text
    • https://saintarseny.ca/sites/saintarseny.ca/files/file/14590415494.pdfIn PDF document text
    • https://www.mftelhas.com.br/adm/Editor/ckfinder/userfiles/files/5461101387.pdfIn PDF document text
    • http://kanalizace-ul.cz/userfiles/file/26694098129.pdfIn PDF document text
    • https://nirmalujjwal.com/public/ckfinder/userfiles/files/86581345063.pdfIn PDF document text
    • https://internationallanguagenavigators.com/media/61672219577.pdfIn PDF document text
    • http://www.icareonline.net.au/ckfinder/icare/files/xodakamimosivij.pdfIn PDF document text
    • https://hfbee.tw/upload/ckfinder_temp/files/20210903235615.pdfIn PDF document text
    • https://glaskunstcentrum.nl/images/file/51465392008.pdfIn PDF document text
    • http://nyett.hk/uploads/news/files/19028266175.pdfIn PDF document text
    • http://heatexchangersolution.com/upload_fck/file/2021-9-4/20210904052812113597.pdfIn PDF document text
    • http://moscow-vernisage.com/files/files/10909035915.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613104551e240---82315842103.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_off0000b667.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB667 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE79 15468 bytes
SHA-256: a22c6fb9079bc310788ba413c56b887e54bcfa4befe694bfa4febeffab2ceb46
font_02_sfnt_off0000f577.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF577 9888 bytes
SHA-256: 7b329f9d0c13382506a339950737b9efef04d55c177ac13de2f4665742e121eb