Malicious PDF — malware analysis report

Static analysis result for SHA-256 438b09634dcc6793…

MALICIOUS

PDF

178.7 KB Created: 2021-09-17 18:29:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: cdfc5c2f39fec759220759a8c8272292 SHA-1: 64099354a4a62c1c234466079c163558db50c441 SHA-256: 438b09634dcc67930fef082ec9e04a6c78554dbacabe67a99dfe2f669268dd32
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF functions as a link farm, directing users to multiple external websites, some hosted on potentially compromised or disposable domains. The presence of embedded URLs and the nature of the heuristics suggest this PDF is likely used as a lure for phishing or to distribute further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://philabc.ru/uplcv?utm_term=comics+batman+pdf PDF link annotation
    • http://xn--m1age8bh.xn--p1ai/files/file/2108308400.pdfIn PDF document text
    • https://pernambucoimortal.com/imagens/files/torizerupujoruze.pdfIn PDF document text
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/8026177296.pdfIn PDF document text
    • https://ph2020.org/FCKeditor/file/2635066448.pdfIn PDF document text
    • http://fslawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/39305549028.pdfIn PDF document text
    • http://professional-tuner.at/uploaded/file/27169938081.pdfIn PDF document text
    • http://impactpluslearning.com/ckfinder/userfiles/files/kofepuvugogopiruvaruzad.pdfIn PDF document text
    • http://ihdbd.org/upload/files/58181127587.pdfIn PDF document text
    • https://efficimm.fr/userfiles/files/68987305266.pdfIn PDF document text
    • https://cbconsulting112.ca/userfiles/files/benivetokupune.pdfIn PDF document text
    • http://vinaktv.com/storage/ckfinder/files/peronefibexokilosusura.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/a28a7ba25a0d5e7506135124b99abe57/bupufow.pdfIn PDF document text
    • http://lulanjina.net/upload/files/bedagajiresixubivijup.pdfIn PDF document text
    • https://artbynela.com/uploads/file/jokimanuluzikifinokif.pdfIn PDF document text
    • https://nucamsa.es/userfiles/files/zonujiwasu.pdfIn PDF document text
    • https://efckrakow.pl/userfiles/file/burubizuxakurenuguti.pdfIn PDF document text
    • http://gewald.ru/content/Files/70379566854.pdfIn PDF document text
    • http://redskap.ru/userfiles/file/sogogevaruzizi.pdfIn PDF document text
    • http://rdmsrl.it/userfiles/files/jatosogodexaz.pdfIn PDF document text
    • http://optimumnieruchomosci.pl/uploads/userfiles/files/27441915128.pdfIn PDF document text
    • https://psychotherapie-coeppicus.ch/userfiles/files/losojalugixilipubave.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136481a30e01---65149046807.pdfIn PDF document text
    • http://sor1310.com/userfiles/file/vasuzagu.pdfIn PDF document text
    • http://kryotherapie.net/neu/userfiles/file/68010831860.pdfIn PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/5349a93cc595361c2baf64693cd45d79/foridunosaxexak.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_off000259d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x259D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000271e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x271E2 19580 bytes
SHA-256: a1d87e3ffdbf42c16b261e71fb203b1596307058e83c79a355c9c76f25182d35
font_02_sfnt_off0002a4ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2A4AB 10672 bytes
SHA-256: 475c7ea9df0d206626b6eb435b20e731c928fcc64f4bf0f8a7fe88b898179cfd