Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a8072d96c127644…

MALICIOUS

PDF

86.2 KB Created: 2021-09-09 18:32:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a80d57ed66dab84efbfc826a314c41dd SHA-1: ded816b4177133534064028290e3bca08e89324c SHA-256: 9a8072d96c12764427f2190c27e0132aa3185749f645e11d4d66ffd8ca411404
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that point to other PDF files hosted on various domains, many of which are flagged as potentially compromised or disposable. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malware. While no scripts were explicitly extracted, the structure suggests it's designed to lure users into clicking links that lead to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://cl-pub.com/files/files/71561534984.pdf In PDF document text
    • http://miass.realxenon.ru/uploads/files/77633747399.pdfIn PDF document text
    • https://rakowka.pl/userfiles/file/8144932666.pdfIn PDF document text
    • http://mebel-moscow.com/content/xuploadimages/file/81758362080.pdfIn PDF document text
    • http://lamexmarket.com/uploads/files/53479078771.pdfIn PDF document text
    • https://khotelmarket.com/FileData/ckfinder/files/20210909_C6A7111F618A938F.pdfIn PDF document text
    • https://xn--80apefbdm9ah5g.xn--p1ai/userfiles/65374402382.pdfIn PDF document text
    • http://harnettcountyhba.com/userfiles/file/wilomimoderul.pdfIn PDF document text
    • http://21cedu.com/pds/userfiles/files/tominewiguge.pdfIn PDF document text
    • http://dwallacelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/10595522047.pdfIn PDF document text
    • http://surausa.com/uploads/files/sinitabapedobu.pdfIn PDF document text
    • https://mlbcsimleague.com/ckfinder/userfiles/files/mikekela.pdfIn PDF document text
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134eca3b78ab---dikogisibubu.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/161375936429b3---tulowak.pdfIn PDF document text
    • http://xn----7sbqwxdbhblh2h.xn--p1ai/data/file/matawukufuzaxadapebep.pdfIn PDF document text
    • https://gmt-tw.com/app/webroot/userfiles/files/xevolakonozivajen.pdfIn PDF document text
    • http://ketnoikienthuc.com/upload/files/85155783413.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/5e7e4d52b841f416591fdf99fa21ee47/lusiv.pdfIn PDF document text
    • http://combatkuntao.com/ckeditor/ckfinder/userfiles/files/varerevuta.pdfIn PDF document text
    • https://eguiders.com/uploads/mowifepes.pdfIn PDF document text
    • http://teedinmaesai.com/user_img/file/zeviz.pdfIn PDF document text
    • http://benthanhsgfarm.net/images/uploads/files/57806759113.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=call+me+by+your+name+book+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_off0000ed0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED0E 10776 bytes
SHA-256: 095fc8e16d3bda22729c4ca84a5cbb9f79c4d1c90031d4de73a1d2e2b97f4dbc
font_01_sfnt_off000105a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105A3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011db5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DB5 17664 bytes
SHA-256: e356c08a7ab14780257fb62dc8807eab417241d683ecb29264c4f7b734e8e8d6