Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec75c5066f3487dd…

MALICIOUS

PDF

86.5 KB Created: 2021-09-12 09:12:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: b1323280d555d3eaceb438e19696755e SHA-1: 69d3f6bed909a2aa8364cecd5a7f950dbbc149f1 SHA-256: ec75c5066f3487dd0a480f34d867b841ff21268d9d757999d76ab7d58a8b1f85
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are part of a link farm hosted on disposable domains, indicating a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly suggest malicious intent. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' confirms the use of a link farm on disposable hosting, likely to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://catamma.ru/uplcv?utm_term=flute+tuning+chart PDF link annotation
    • https://koltoztetes-szallitas-lomtalanitas.com/ckfinder/userfiles/files/vinuterimosixe.pdfIn PDF document text
    • http://uhy-th.com/image/upload/files/zodoligaditufojig.pdfIn PDF document text
    • http://planetamama.ru/files/file/zizabomenidunuzuzudexidob.pdfIn PDF document text
    • https://mintedimages.com/ckfinder/userfiles/files/92970285462.pdfIn PDF document text
    • https://zegaoyun.com/calisma2/files/uploads/babonegalogupar.pdfIn PDF document text
    • http://toflight.mobi/attachment/ckeditor/files/0d1e1e0f49bfe5f72f67b6616fd11156.pdfIn PDF document text
    • http://gardenofsound.com/userfiles/files/zawibitakinotufopebig.pdfIn PDF document text
    • http://santeh.md/img/files/bumeji.pdfIn PDF document text
    • http://terminsk.by/pics/files/wevajewusubunowote.pdfIn PDF document text
    • http://olymp-kiev.com/temp/fckeditor/file/67770077203.pdfIn PDF document text
    • http://1-champagne.com/blog_images/blog_/file/rupeg.pdfIn PDF document text
    • http://fusiongrup.ro/userfiles/file/lekufevunelulofoniza.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138ad2b8e3ee---dipuvedakenugedida.pdfIn PDF document text
    • https://szekszardportal.hu/userfiles/file/16097324897.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/bc355bf88e7a37fc01b511d26baed344/kuzutasekaxexe.pdfIn PDF document text
    • http://bright-mineral.com/uploadfile/file/2021090204571422.pdfIn PDF document text
    • https://nepalipublisher.com/ckfinder/userfiles/files/nikuguk.pdfIn PDF document text
    • https://soccerauquebec.com/userfiles/file/32430018877.pdfIn PDF document text
    • https://tonycustomtailoring.com/nbloom/fckuploads/file/54503423301.pdfIn PDF document text
    • http://around-sicily.net/userfiles/file/kabebametibemuf.pdfIn PDF document text
    • https://kermoulin.com/userfiles/file/podebavisunibibov.pdfIn PDF document text
    • http://cattaneoarchitetti.it/userfiles/files/tedijireselifewuw.pdfIn PDF document text
    • http://bridgeonlaw.com/filespath/files/20210910101139.pdfIn PDF document text
    • https://gitedu.in/ckfinder/userfiles/files/14261488525.pdfIn PDF document text
    • http://myflora888.com/ck_files/files/nemepaxafonitijoluxu.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_off0000ede8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDE8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000105fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105FA 18172 bytes
SHA-256: f6b68bba45f8d9f4f4c860c004226e358d41091ee3a89156ef81cca59eea6566
font_02_sfnt_off000135a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135A6 10300 bytes
SHA-256: 6643a4e6a9e6a2ca1cdeea1e38ab84e9eeb6f6613bd79d6fb3fd7ab738fc3bb0