Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fbf35bc36c8ffa0…

MALICIOUS

PDF

74.9 KB Created: 2021-06-11 11:34:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 98e3b62aaab7780b2606e6a2928f4390 SHA-1: b22442f9dbcf3904701a5b500c91fdeccf602029 SHA-256: 8fbf35bc36c8ffa0aaac7ebe7f1670c64e674f9033f8b8b534119e5bfab26302
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://queure.ru/uplcv?utm_term=possessive+and+adjective+pronouns+exercises PDF link annotation
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c26898e61f7---812902344.pdfIn PDF document text
    • http://extracam.es/app/webroot/arxius/file/xenafebunulipabujosudev.pdfIn PDF document text
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/o9g9ui99j4fvd6kistt2kvtg44/josewabexon.pdfIn PDF document text
    • http://capri.lt/userfiles/files/wivesilowagodanuzaxurugaf.pdfIn PDF document text
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607248c0d2b34---tetivutujedavevifoz.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/7307a48162b06fa15c17b57b84859378/33870967605.pdfIn PDF document text
    • https://gbagencement.fr/uploads/file/tazawexekononepajotojisa.pdfIn PDF document text
    • http://tivatijapan.com/uploads/userfiles/file/pagum.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/1i98cr99bed3kpd26hovn3gdb5/wolamunarate.pdfIn PDF document text
    • https://cal.lighting/wp-content/plugins/super-forms/uploads/php/files/382533f3aa74a72ca634f562159a8713/wibuwarifonodid.pdfIn PDF document text
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/36714b4816aa2b3ddd3f35f0aab35733/96367543411.pdfIn PDF document text
    • https://hse.tw/upload/file/60279006943.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/c002f342c081b410dbb7b191abe47adf/vanisifusa.pdfIn PDF document text
    • http://theettiaresmontreal.com/clients/f/f0/f03dfc1790708d0b03c48e9879ef2ea6/File/sabomijakebozomanoxirova.pdfIn PDF document text
    • https://expeditions-travel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b1c5bc7d75---ridatele.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e7f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7F0 5240 bytes
SHA-256: c71fc0bebab14f7f3f6f56ef396a62601d8b9551c890723e45ef36be3e7c7bdb
font_01_sfnt_off0000f9e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9E7 10860 bytes
SHA-256: 80c5d16134f7e805abc2cd06a90676534019634e9bafe3c848f839a9a29be6b7