Malicious PDF — malware analysis report

Static analysis result for SHA-256 87753bbf6cb0e439…

MALICIOUS

PDF

77.8 KB Created: 2021-06-21 11:57:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 2e98530bf5f121cd65f2a4009e4fd293 SHA-1: 7c701da33ea86f7f2e86a4395d9c3333a8a20195 SHA-256: 87753bbf6cb0e439e5e88aa519b4bd074a49fe2e906bd163c1911e8eba761e53
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and a machine learning classifier. It functions as a link farm, containing numerous URLs pointing to various websites, many of which appear to be compromised WordPress installations. The presence of these links suggests an attempt to manipulate search engine results or redirect users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/4t29eh95t82vqpk41o6eslbhm1/39662290885.pdf In PDF document text
    • https://menlopark.com/wysiwygfiles/file/lepulese.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082599d1f924---41935720688.pdfIn PDF document text
    • http://banhangcongnghe.com/upload/FCK/file/17764959037.pdfIn PDF document text
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/8bneaecs7nkcp1jeho7e2onr1r/48794350373.pdfIn PDF document text
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160986a268c82d---moxivumakuwirotazi.pdfIn PDF document text
    • http://bhs1966maui.com/clients/64750/File/74574562233.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2d14ec3cea---tawovesupobebanir.pdfIn PDF document text
    • https://festival.bg/fckeditorfiles/file/17617298906.pdfIn PDF document text
    • http://www.companyforte.com/imagenes/editor/file/bidobubojetibemugomalu.pdfIn PDF document text
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/u1cuu7h7ge01au9k051f0katf1/dasodifepifisux.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa2b332646d---23818971054.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1897d7c7bc---59873520417.pdfIn PDF document text
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/maqnm61g5a4th33o198p731lk2/13736933361.pdfIn PDF document text
    • http://laweasy.kr/userfiles/file/50164001501.pdfIn PDF document text
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/ac837313188076c7d4e62a07d693b2a0/dunoke.pdfIn PDF document text
    • https://sealskinz.ru/files/file/52599843947.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=connect+iphone+to+blue+yetiPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e94d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE94D 4684 bytes
SHA-256: 3e09d9a94929c09587f60103ec6c00f40fb853283e1efda7880a7636d3cb8ea8
font_01_sfnt_off0000f937.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF937 2484 bytes
SHA-256: b90db19c2f777b7dc0b707ba2317d3983e4e68eda5e0f6ca056e06946e48e157
font_02_sfnt_off000103d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103D5 11104 bytes
SHA-256: 4f43c64213176549c2d5001f65285beec20ab0ed4a0879767f140e3823e45798