Malicious PDF — malware analysis report

Static analysis result for SHA-256 0237b145b7dee93b…

MALICIOUS

PDF

82.8 KB Created: 2021-09-06 09:36:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ae04825a1a02b8cc771bc2f0a3308635 SHA-1: 315cdacdac550db3c49f5b1b79f8ea9abb9e8702 SHA-256: 0237b145b7dee93b59c8a4135ce835c70f6ddf24439144e8e2cedb0fa92d590a
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised WordPress sites. These sites host further PDF files, suggesting a multi-stage download or redirection scheme designed to obscure the ultimate malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://call.ae/wp-content/plugins/formcraft/file-upload/server/content/files/1606c960de3b14---kepog.pdf In PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610460d6d0f87---55612877739.pdfIn PDF document text
    • https://fotoprint.lv/downloads/file/32868054253.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8ef77e5153---notejorunebavezetuximu.pdfIn PDF document text
    • http://ues-rb.ru/themes/ues-rb.ru/files/97958627443.pdfIn PDF document text
    • http://fittbikese.hu/files/file/37989895210.pdfIn PDF document text
    • https://liniagdanskzydowo.pl/files/nonevir.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160e19802f1c81---zukofimo.pdfIn PDF document text
    • https://binarbaidservices.com/public_html/userfiles/file/joletimukojexukurik.pdfIn PDF document text
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/410907c1ab30e08b1a2d20f2d58af0e5/basefovexasabukodikew.pdfIn PDF document text
    • https://everywheregenes.com/uploadfile/qu26_qu106_com/files/52313316341.pdfIn PDF document text
    • http://nuestratierrapremios.com/campannas/file/gunamaxaluvegibinuja.pdfIn PDF document text
    • http://bonfiremadigan.com/uploads/fckeditor/file/42983335514.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/160e77c9965f09---82944447485.pdfIn PDF document text
    • http://change4best.ru/upload/file/rivefazanirarejapubiwav.pdfIn PDF document text
    • https://on-call-anatomist.org/ckfinder/userfiles/files/vaxudubu.pdfIn PDF document text
    • http://dbjhockeytournament.com/clients/f/f9/f9ff496842c877cbb4522510b668f2a2/File/1716456565.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160ee0dc5a366b---gomonojaruzorilurikadaw.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/160c94e5069ea8---87807503936.pdfIn PDF document text
    • https://mariapolis.net/ckfinder/userfiles/files/93550143755.pdfIn PDF document text
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/a2eb9e470c042725c6b2e68c9f5273a0/lopopisujo.pdfIn PDF document text
    • https://www.artikel238.nl/emmwebbit/resources/ckfinder/userfiles/files/xawamowasobazak.pdfIn PDF document text
    • http://www.sandzthabapanel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b590f7b79ec---vekuwites.pdfIn PDF document text
    • https://alternativecarrepair.com/userfiles/file/jowafiwezemetu.pdfIn PDF document text
    • http://homespakistan.net/magzine/uploadfiles/file/5119446704.pdfIn PDF document text
    • https://www.agcontraincendios.es/ckfinder/userfiles/files/38184333519.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=ubuntu+server+terminal+commands+pdfPDF 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_off0000dbe6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBE6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f3fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3FD 11096 bytes
SHA-256: 1763afd6f8105b625d2be540228dcf79468273008d7121f071bfdeccc820f1e2
font_02_sfnt_off00010da8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DA8 18552 bytes
SHA-256: 9c5087e854ff644e53cb1021ac1d261b53c43a0ca0bf4c33223dde42511b5d26