Malicious PDF — malware analysis report

Static analysis result for SHA-256 dff2e663b37609b4…

MALICIOUS

PDF

76.6 KB Created: 2021-06-10 01:47:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: dd2d8f7fa53dc0bf7761f3d42dd3a24e SHA-1: 935a0f6e85a1cd4ff4cd288666d8b9ef16d74215 SHA-256: dff2e663b37609b44236131d3adf29abbc0097f55768995d7fec4754756efb53
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-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.
  • 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://infrive.ru/uplcv?utm_term=dishoom+full+movie+download+mp4 PDF link annotation
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/c4c637f6f2ed5a6afa2942a3554790b6/kuvarixokekitedivotesije.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/f575372c87db1c5a99d0083d4ce4947f/worujuwanux.pdfIn PDF document text
    • http://surrattsville69.com/clients/8/81/8122276c22396d7fa0996010cc369f50/File/notas.pdfIn PDF document text
    • http://baohanhranghm.com/upload/img/files/fekejatujabemejesagem.pdfIn PDF document text
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/c1a1b365725b9a9017c616fcb8422e05/nenepemuvo.pdfIn PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1606d122258cfa---25155698274.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab35265ad98---muxoputuwoxewepojapazetaw.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160ae5b495faef---xowumelijakabolul.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/9264fc3d75896e73b66bfb753faa91bc/6266576149.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/dd2a16854bf34e86b24e066c5ac88202/rizibesowagodewixew.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160bfb3fbec62a---riborarigodokonuxaxis.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/f260b289c844c5f79127e3c59fd635b3/binuponitinutimasubobiw.pdfIn PDF document text
    • http://rockpapersun.com/upload_mce_image/file/43932906143.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/vj2emc69fe5gfjdrq3e2dronf3/88088283427.pdfIn PDF document text
    • http://www.bandungmesin.com/file/22846269710.pdfIn PDF document text
    • https://hpx.com.ua/wp-content/plugins/super-forms/uploads/php/files/8c09fc58870b3986fea9a4ab63c64991/76973191224.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_off0000ee87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE87 5424 bytes
SHA-256: 2ae0804fca1faae42552ae3dde61731e1bb7122f8961cfbebf09db4b6c2f5503
font_01_sfnt_off000100f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100F9 10628 bytes
SHA-256: ab7ff87f4e192e3972a01b4b1956d1612b2315df692c2e9760662d070a08fb42