Malicious PDF — malware analysis report

Static analysis result for SHA-256 78d6eef3c508d845…

MALICIOUS

PDF

90.3 KB Created: 2021-07-16 07:29:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 890f01ec6fd8b59555dc566d14e40054 SHA-1: 3c1d16d7e8d09948cd417938a75a76b8e827d0a1 SHA-256: 78d6eef3c508d845b104dfe94893bda2246bf953f5a48474f46bce2b0b5391cd
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous domains, many of which are either compromised or appear to be disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded URLs and the heuristic firings related to link farms and compromised CMS uploads support this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://zuche0551.com/upload/file/darivuke.pdf
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608768ef2d0cc---zuxivawomajonulalipaseb.pdf
    • http://studioscoponi.eu/userfiles/files/fijuvafudezatetatek.pdf
    • https://carcarnet.com/home/sandbox/domains/hkdance.tritek.hk/public_html/ckfinder/userfiles/files/76728066005.pdf
    • http://olversonfamilyreunion.org/clients/5/51/51a48c89da211807e19ed56f8a1a1822/File/pitokotani.pdf
    • http://p-itos.net/admin/userfile/image/file/setem.pdf
    • https://acryl-bg.com/userfiles/file/46489888866.pdf
    • http://dragonera.cn/admin/userfiles/file/nebazorapagakubepuv.pdf
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/dc82f13297f4b4058ad11e4a496cd0ef/kapesago.pdf
    • http://vietnam-intraco.com/webroot/img/files/20925786963.pdf
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160770e9e342fd---22173935180.pdf
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1609d2f45a9238---56971630123.pdf
    • http://kiszelyugyvediiroda.hu/docs/file/makaxig.pdf
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16070773a574d6---14828637561.pdf
    • http://crosswaysrecruitment.com/userfiles/file/94764651447.pdf
    • http://ankurgroups.com/userfiles/file/36079916379.pdf
    • http://rutherford58.com/clients/5/5b/5b2824e44de76337c32dfcbc3ee6dba3/File/legatozetopemutob.pdf
    • http://adams-gold.ru/archive/image/file/71515664948.pdf
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b5994f42021---37975074872.pdf
    • http://scro.ru/pic/file/1159635038.pdf
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/44nvub77dgj8f46b8dn6oc2850/babexidizajur.pdf
    • http://rw-hse-businessconsulting.de/userfiles/file/vegababupag.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/160e05f91d9c83---62070901596.pdf
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/16099dd3f14529---70719806893.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=crow+cawing+outside+my+window
    • 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_off0000fc49.bin
6a0b21a31c5e069c88985896b39b4c64120926705c32ebb1ed006599bca3e874
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC49 11000 bytes
font_01_sfnt_off000115bf.bin
368b070d007e91b344241d3c8aea6ae6fcd990614655e1a6ccedd84ad92379c8
pdf-font-stream PDF embedded font (sfnt) at offset 0x115BF 17584 bytes
font_02_sfnt_off000143da.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x143DA 16792 bytes