Malicious PDF — malware analysis report

Static analysis result for SHA-256 81da980dd94394d1…

MALICIOUS

PDF

92.6 KB Created: 2021-07-30 09:01:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 26e217d4b83246984aaf805596f24318 SHA-1: 821fb228829cffa000ea7f0e98f72c4fdc05f64f SHA-256: 81da980dd94394d19fcfc0a23554ec9810f20305daa35e655df01066af18f07d
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing to multiple unknown URLs, many hosted on compromised WordPress sites, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to exploit users via these links. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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 https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16098bb2f256c3---93435292258.pdf In PDF document text
    • http://cobbpaynefamilyreunion.com/clients/862770/File/1000724162.pdfIn PDF document text
    • https://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1608c5a303266b---totiwazuzuxeseneb.pdfIn PDF document text
    • http://kapalishakti.com/ckfinder/userfiles/files/jiwamibiga.pdfIn PDF document text
    • http://shepardinteriordesign.com/rw/upload/file/28228191137.pdfIn PDF document text
    • https://dafelia.com/files/sexin.pdfIn PDF document text
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/160faee93cb929---34076745069.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4b73f7c02b---valesoziwaxerugepokox.pdfIn PDF document text
    • https://zahnersatz.pl/userfiles/files/gidevebawakevo.pdfIn PDF document text
    • http://rockycheng.com/ckfinder/userfiles/files/pizakukuwovigeze.pdfIn PDF document text
    • https://www.masismarketing.com/wp-content/plugins/super-forms/uploads/php/files/2e9383b5ddb01babdbc497a66927ce0d/83048975450.pdfIn PDF document text
    • http://horizonpestservices.com/userfile/tikoduxogorobozevo.pdfIn PDF document text
    • http://staging.impactredevelopment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3f088a845e---950131752.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/pogukewoputijisi.pdfIn PDF document text
    • https://bunyaminerdemir.com/resimler/files/dilavabatalap.pdfIn PDF document text
    • http://dioceseofniranam.org/userfiles/file/91006524013.pdfIn PDF document text
    • https://ilc.ua/wp-content/plugins/super-forms/uploads/php/files/0p6ad8as3kkkbpgbsnivg8viv2/71992125909.pdfIn PDF document text
    • https://wecafephuket.com/wp-content/plugins/super-forms/uploads/php/files/5gdmgjn1dgdl5sh07sq5vo3764/78780603487.pdfIn PDF document text
    • http://agnieszkapawlik.com/userfiles/file/gewapozegorovidalu.pdfIn PDF document text
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d1d0184835---20229906848.pdfIn PDF document text
    • http://gibisch.info/files/files/fodumuru.pdfIn PDF document text
    • http://xn--clinicaquirogavilario-vbc.com/wp-content/plugins/super-forms/uploads/php/files/jr2nvulf248api1srqr9nrvn76/dirafo.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/ae6b8d1e8c48c09182a8478418256c9d/kexizavukulugidanev.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8d2b92ac53---kuxenumupodovi.pdfIn PDF document text
    • http://aldara-latinoamerica.com/userfiles/file/fexolezefepili.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=which+smart+tv+have+bluetoothPDF 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_off000105f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105F3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011e0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E0A 10688 bytes
SHA-256: e807f146aa5de4ae4d176ba6e401cf29d655ad929fc86bb0b5aa476881ce3ac0
font_02_sfnt_off0001369a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1369A 17024 bytes
SHA-256: 0c1dbff5db7a14e9cd489c1d5d5b11bff5f221c02603e212f84f094e654a13e9