Malicious PDF — malware analysis report

Static analysis result for SHA-256 61909ca4fb71e5db…

MALICIOUS

PDF

74.9 KB Created: 2021-06-14 22:58:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 0a18a8b4d3717f2e70e7ed2bcb5866f1 SHA-1: f7e3c3afa324cd609150db6bff5e5ac34630714b SHA-256: 61909ca4fb71e5dbfaa84d91f59648870604a332495b36021148abc47df3d51b
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://nomylo.ru/uplcv?utm_term=telugu+latest+movies+free+download+tamilrockers PDF link annotation
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0a10fc91e7---1518655857.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/f96aa83aa63e25a4bd87f062b9926b28/81343487911.pdfIn PDF document text
    • http://aclamerica.com/customers/CMS-IMAGES/file/fulew.pdfIn PDF document text
    • https://www.tangelo.no/wp-content/plugins/formcraft/file-upload/server/content/files/16081a8e696c1c---tibadetutivupi.pdfIn PDF document text
    • https://associazionedynamica.it/uploads/file/nigufuvobaj.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/160bd4c5902eb7---xifoturadope.pdfIn PDF document text
    • http://ristoranteibucanieri.it/userfiles/files/tekiz.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/63f497e2f957541940900b8ed1f24d3b/29272953741.pdfIn PDF document text
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/fdfa2b5d63c4db3658d1a99a43cd5f0b/23014952471.pdfIn PDF document text
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/m45c6b54uq16heh3dokfa8aldv/begexedivivijivi.pdfIn PDF document text
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7654313a23---25362133423.pdfIn PDF document text
    • http://yangs-ns.com/ckfinder/userfiles/files/20210528014359.pdfIn PDF document text
    • http://zhengfutz.com/v15/Upload/file/202152821632856.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/4e13189a4051b00366290b3e34e84440/58488751022.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160726dcb003ad---sibupudoxudunuxu.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_off0000e72b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE72B 5508 bytes
SHA-256: fcd4cb40be72a30460fd07f463ba616e0daed2e25d7940c1912cd42662c6ab54
font_01_sfnt_off0000f9ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9EC 10760 bytes
SHA-256: 5ec516f7ac5214c660c1f6e18c3053d54a20acaa2d7900f7db8628232331a645