Malicious PDF — malware analysis report

Static analysis result for SHA-256 93ef61711c5793b2…

MALICIOUS

PDF

74.7 KB Created: 2021-09-11 08:46:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 5b00452586abf8628cf0d9d885c3f8db SHA-1: 1da203660fa6ec46eb00dc1f8d2f5b3204c7fc4c SHA-256: 93ef61711c5793b2b616ba5993858562fcb17e0870089a43ea56a73798c1fcb1
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to domains associated with link farms or compromised content management systems. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and does not provide direct textual clues, but the heuristic findings are sufficient to determine the attack pattern.

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://apicn.net/upload/files/lijolade.pdf In PDF document text
    • http://icsbc.ru/fuploader/file/57470108036.pdfIn PDF document text
    • http://kbinteriery.cz/userfiles/file/wowokemizag.pdfIn PDF document text
    • https://aukshanya.promosing.com/alpha/ckfinder/userfiles/files/renadewogopegusex.pdfIn PDF document text
    • http://stellarvvv.ru/ckfinder/userfiles/files/lipabuxuzevutategofixaru.pdfIn PDF document text
    • http://abw10thstreetne.com/uploads/files/jutiwuz.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613135b0a2ba4---suvevudotapodamaxovusaru.pdfIn PDF document text
    • http://makeyourpartnermelt.com/userfiles/file/23126085845.pdfIn PDF document text
    • https://lifesmart.lifesmart.ro/ckfinder/userfiles/files/14463447340.pdfIn PDF document text
    • https://bloomlight.pl/_bloom/file/31787226964.pdfIn PDF document text
    • http://xn--j1aii.su/userfiles/file/rekokowik.pdfIn PDF document text
    • https://totalsewa.com/userfiles/file/9512361399.pdfIn PDF document text
    • http://oldmotorsclub.com/files/file/36443393872.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/161382e0596e6a---47780502074.pdfIn PDF document text
    • http://pawsandtiaras.com/ckfinder/userfiles/files/pilatepusofezufiwifer.pdfIn PDF document text
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/e52838e6748d8bb02350c50ace33d562/26333832010.pdfIn PDF document text
    • http://xn----7sbicwad4afgcgd5aph7d5e.xn--p1ai/ckfinder/userfiles/files/51216122763.pdfIn PDF document text
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/1rhlhgddqap7pe3bogaqb40doj/50714249463.pdfIn PDF document text
    • http://gzafjc.com/uploadfile/files/22216104547.pdfIn PDF document text
    • http://erpos.sk/data/files/butakuxazadodebodaz.pdfIn PDF document text
    • http://netichikawaya.com/userfiles/file/negutorat.pdfIn PDF document text
    • https://herfection.herfection.tw/upload/ckfinder_temp/files/20210902195826.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=billiard+apk+downloadPDF 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_off0000c088.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC088 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d89a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD89A 17580 bytes
SHA-256: 095b3d908e96e9d176280043e56f6ad0e2f265ed5f5813dccbae7b018341fefd
font_02_sfnt_off00010671.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10671 10216 bytes
SHA-256: a889373a40ac4c841d914d75f41512e6b340a754a7a04e22ea3fa12ac2a354fd