Malicious PDF — malware analysis report

Static analysis result for SHA-256 d18635cd797dd2f6…

MALICIOUS

PDF

87.2 KB Created: 2021-07-02 13:46:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 2b0b7404caad5395787ba200e91eae72 SHA-1: 47d9f6764929d87163e48a149c95023ef0d6495d SHA-256: d18635cd797dd2f6467a64793ffcee7c2c261acf6e4c6c9f027bc794d7eb1faf
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The primary function appears to be redirecting users through a series of links, potentially to a final malicious payload or phishing page.

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 https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/cmjj72a3bm6t4qhbk0dfbn0mhf/63509734156.pdf In PDF document text
    • http://al-bandak.com/userfiles/file/97127369280.pdfIn PDF document text
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607996f25517b---fakafawuk.pdfIn PDF document text
    • http://alhouti.com/userfiles/file/wilonivudaxivafizixaxuvew.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607d02e145fa5---buzetijugimatevigumo.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/iuadro7o83r53veajg0ea0kuu7/suxosekoxamiw.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/160a3461e2863d---59623705171.pdfIn PDF document text
    • http://www.aportecnica.com/imagenes/editor/file/80458427363.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1607cb7bc373a7---51502470083.pdfIn PDF document text
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/0cd9166c7d0f490d61e8f89c79497c39/40588080264.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7b70eceda---38846761443.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/tm6uvnqjujsod5u6kmvau6ap0r/46970314979.pdfIn PDF document text
    • https://www.mnspineandsport.com/wp-content/plugins/super-forms/uploads/php/files/af89e71ab9bb3fa86e9931bc33778a40/7754032250.pdfIn PDF document text
    • http://augustaelectricalwork.com/editorData/file/wuwadazexepaxigagumifamum.pdfIn PDF document text
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160988e8743792---migiwijerivuw.pdfIn PDF document text
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/0fa9f094c8135eb2d4369ec663778b14/buzosobetazafimumikokute.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/160783b253a05e---sozunonogo.pdfIn PDF document text
    • https://rubin2000-distribuitorshop.ro/userfiles/file/17703923804.pdfIn PDF document text
    • https://bwawarszawa.pl/upload/file/dawisodilapuxisutiweno.pdfIn PDF document text
    • http://zs-oilfieldequip.ru/d/files/852940163.pdfIn PDF document text
    • http://amon-syotengai.com/userfiles/file/jasuk.pdfIn PDF document text
    • http://sl-light.ru/design/img/upload/file/60896522992.pdfIn PDF document text
    • https://burlingame.com/wysiwygfiles/file/xolubilexome.pdfIn PDF document text
    • http://leakefamilyreunion.com/clients/63964/File/36476867477.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb174ee72c---23702584445.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=the+mass+of+one+mole+of+a+pure+substancePDF 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_off0000ee60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE60 17724 bytes
SHA-256: 22d8909ada6e412bcc9d7f676202edf87c64ec763d04fe16f23e2d136f4dfeba
font_01_sfnt_off00011c86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C86 10856 bytes
SHA-256: a1a8e5417c7b0c2d277530b1341a5400fbd54d0e931892f56118ee8c01389ca0
font_02_sfnt_off0001353a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1353A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1