Malicious PDF — malware analysis report

Static analysis result for SHA-256 28ac325d9a1c3ee3…

MALICIOUS

PDF

106.4 KB Created: 2021-06-28 02:53:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8400d585c31062a12ed8b44b57668f8d SHA-1: c23a6efaaa464c5fbea247e4ebf1bb15bf10230c SHA-256: 28ac325d9a1c3ee307ba6cf7b281750f042684c110db9609427a7557baf70a24
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF document was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains a link farm with numerous URLs pointing to various domains, many of which appear to be compromised CMS uploads or disposable hosting. The primary purpose seems to be redirecting users to potentially malicious content, consistent with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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 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://knshzj.com/CKEdit/upload/files/bulajejewu.pdf
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a12b2ece59b---77233595188.pdf
    • https://gretajensen.com/ckfinder/userfiles/files/xamizogomalekikikovaxojuj.pdf
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/2252d0c01edf4ef5d3ae5dc031bc3932/bowozojugazurinosalig.pdf
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b7d229b0fd2---45770046207.pdf
    • https://alakharia.com/public_html/userfiles/file/41823803211.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/uqfjbbddc9a280sb5rquiiktl5/64116015187.pdf
    • http://www.look4job.gr/images/_user_na/file/ninitufijus.pdf
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/da33634ae50fd1f7c22c9c6bb505a625/vosez.pdf
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c430f16e21f---piwebu.pdf
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/0g3l9puh6deqt91jdu1jiocq5d/xekevibekikudowenizoli.pdf
    • https://nanyangtextile.com/userfiles/file/80641667310.pdf
    • https://amrapalispot.com/userfiles/file/75603704562.pdf
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/05a7d8dfbae29129d33186e87e62ae88/vakabewitajuzasu.pdf
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160708d4f150d0---zerogitugekefo.pdf
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/63d406a3779a54c13c49c24cc12bae0e/biwigigebutejinabofetu.pdf
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b6f9650f62e---mibunazapuzer.pdf
    • http://springhs1988.com/clients/a/a7/a70db2535ed58991dd9724faf9b165d0/File/23647926301.pdf
    • http://getem.pl/files/file/wozigefonakizifinovone.pdf
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/772902hg7es191vc2reems8bp4/21698924973.pdf
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608167deb03d6---lotivogufapoleso.pdf
    • http://csc0516.com/userfiles/file/20210609121539_2wfhgo.pdf
    • https://aihr-iadh.org/uploads/FCK_files/file/zavupolemizesa.pdf
    • https://rclurie.com/wp-content/plugins/super-forms/uploads/php/files/9d10d2676cedff9554e2f7f7d5215958/55600006575.pdf
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e316d5822b---73063925786.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=knot+tying+honor+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001416f.bin
6c66539e419241da891427286a772decb582cf2ae112da07ad8011a3dd973929
pdf-font-stream PDF embedded font (sfnt) at offset 0x1416F 10376 bytes
font_01_sfnt_off00015893.bin
f2e01559704f0d49adc829a4bf430bbfef2fe4084fc392d6e6ed16b783d3ffcb
pdf-font-stream PDF embedded font (sfnt) at offset 0x15893 16856 bytes
font_02_sfnt_off00018417.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x18417 16792 bytes