Malicious PDF — malware analysis report

Static analysis result for SHA-256 b85e56ef22b5ff67…

MALICIOUS

PDF

90.9 KB Created: 2021-08-24 18:42:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 3038e66a4d350dc3eec3587a0592feb1 SHA-1: 1471de05ab77dd25e9f7147b5c427e2d88e81bde SHA-256: b85e56ef22b5ff67c5593bbfcf32385b3d581f25c8b45e9f075772079c197742
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristic analysis revealed that the PDF functions as a link farm, containing numerous URLs pointing to potentially compromised websites or disposable hosting. This suggests the document is designed to redirect users to malicious sites, likely for phishing or malware distribution, rather than for legitimate content consumption.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://infrive.ru/uplcv?utm_term=simple+sentences+in+english+daily+use PDF link annotation
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160874646ac53d---9112177567.pdfIn PDF document text
    • https://cabsfromheathrow.com/userfiles/file/54070746743.pdfIn PDF document text
    • http://e-skala.pl/userfiles/file/85652144539.pdfIn PDF document text
    • http://studiomarazzi.eu/userfiles/files/tedowivegimesesemitogub.pdfIn PDF document text
    • http://wmc21.com/ckupload/files/71480338721.pdfIn PDF document text
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/2ba1fe7d50c796341b1a2a31289001a3/puvuwafovew.pdfIn PDF document text
    • http://myconnect-thailand.com/image/upload/File/96655748774.pdfIn PDF document text
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d829ed3177---19879273096.pdfIn PDF document text
    • https://handinhand-daycare.com/ckfinder/userfiles/files/31666715921.pdfIn PDF document text
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/evikv6g2o3qg02us88su5qa2e5/fijumulozegosofexabi.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5a7lo7661nmbl1ofktgo3u0pc3/fozuforijufunile.pdfIn PDF document text
    • http://afgventuregroup.com/cfiles/file/lovuzuribemekokab.pdfIn PDF document text
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/83dc00cfdae8fccc6ab2f6409528f084/59907663061.pdfIn PDF document text
    • https://hitpoint.tw/userfiles/file/69445367577.pdfIn PDF document text
    • http://grandp.ru/userfiles/file/26375032384.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/b8b7095f32fef1a8b9b2a0e46c5bf920/vizodiwajav.pdfIn PDF document text
    • http://yossy.biz/userfiles/file/98287959934.pdfIn PDF document text
    • https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/rptir944o8slsnb30ue50v9ia1/75651831324.pdfIn PDF document text
    • http://srihemkuntschoolint.com/slbdavbatala/userfiles/file/49068705644.pdfIn PDF document text
    • https://ruedi-leuthold.com/userfiles/files/65457469938.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/dadd753b21a3b15e40bf538524906f25/36315158562.pdfIn PDF document text
    • http://poetische-malerei.de/web/editor/files/92779335352.pdfIn PDF document text
    • http://www.kymkarajok.net/tiedostot/files/15230916214.pdfIn PDF document text
    • https://tranhdaquyhn.com/uploads/news_file/25592231725.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_off0000ff2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF2B 11032 bytes
SHA-256: 9221c50e3199b7744032f439d1fb29255e28972ae7e793d493b77230551e2266
font_01_sfnt_off0001186a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1186A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001307c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1307C 17504 bytes
SHA-256: ff46007f020e538e267007217d5e9b20fc793b5affe1faac4b3e3a7bf7920b89