Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ef2b28ff234c304…

MALICIOUS

PDF

80.9 KB Created: 2021-09-16 13:43:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: a1cee05a20a0dcfb9ee32a500c972e0f SHA-1: 31263223cd02e8173353bc691adf7ab839af6e93 SHA-256: 4ef2b28ff234c3042272ed4e0008456194a2c3d91f96c239663ce0fff7f97244
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on disposable domains or compromised CMS instances, indicating a link farm designed to lead users to malicious content. ClamAV and ML classifiers strongly identify this file as a malicious phishing trojan, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://enewind.com/pliki/file/nekedun.pdf In PDF document text
    • http://aedelsur.com/contenido/files/50519594429.pdfIn PDF document text
    • http://vstarmp.cn/upload/files/20210909_121127.pdfIn PDF document text
    • http://tianlanip.com/filespath/files/20210907135039.pdfIn PDF document text
    • http://around-sicily.net/userfiles/file/webilofetuzubo.pdfIn PDF document text
    • https://parlagame.net/calisma2/files/uploads/rufavamonux.pdfIn PDF document text
    • http://zhongjiukeji.com/upload_fck/file/2021-9-14/20210914110911641752.pdfIn PDF document text
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613c3f6645721---12022922575.pdfIn PDF document text
    • http://ltptech.vn/uploads/userfiles/file/24050207221.pdfIn PDF document text
    • https://psfund.org/public/uploads/files/cms_files/9574297774.pdfIn PDF document text
    • http://studiotecnicopinto.it/userfiles/files/88441417722.pdfIn PDF document text
    • https://zlataraburmevuckovic.com/files/fizuvuz.pdfIn PDF document text
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/b08680a72d0f40482815957d35182516/99427899712.pdfIn PDF document text
    • http://ytovietnam.net/ckfinder/userfiles/files/99166997029.pdfIn PDF document text
    • https://tempatpasang.com/contents/files/muposidepejitevuxomob.pdfIn PDF document text
    • https://aitalk.vn/upload/files/nibidatadipeb.pdfIn PDF document text
    • http://art-lan.ru/uploads/assets/file/69281568174.pdfIn PDF document text
    • https://eghamatyab.com/basefile/bainbookcom/files/26079684711.pdfIn PDF document text
    • http://sbmhavacilik.com/userfiles/file/fuxefafaguv.pdfIn PDF document text
    • http://master-br.ru/img/file/3584335416.pdfIn PDF document text
    • https://nistd.in/userfiles/file/vofeveleta.pdfIn PDF document text
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/bee2ded864eed43d998f832b63a7216e/62710117141.pdfIn PDF document text
    • https://kop-trans.pl/uploads/userfiles/files/36036273843.pdfIn PDF document text
    • https://adverto.ee/userfiles/file/ladawudixutopedenof.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=2+player+games+for+android+onlinePDF 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_off0000d7b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7B1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000efc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFC8 10880 bytes
SHA-256: 87ad83459603417e2c98787206757747c2fa36d77113dedc3d01608f513631e5
font_02_sfnt_off000108bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108BC 17312 bytes
SHA-256: 93d35580978497fea07ef832377e712a71b4063a1598296ff0cb6a9bef9331bd