Malicious PDF — malware analysis report

Static analysis result for SHA-256 35bcee9660278c6f…

MALICIOUS

PDF

84.5 KB Created: 2021-06-18 01:59:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 3037c7e72813fca3dcc5973b6ba9638c SHA-1: 5e7378da3684317bb47a134ab73b6b3a118f2573 SHA-256: 35bcee9660278c6ff3dc2e75556635909942c36066c55255ec62d758b1e0c2f8
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites and disposable hosting, indicative of a link farm designed to redirect users. The heuristic firings, particularly 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM', strongly suggest a phishing or malware distribution attempt. The ML classifier and ClamAV detection further corroborate the malicious nature of this document.

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.findvoters.com/userfiles/file/85089918956.pdf In PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/4a4465b26b55c09e7a5e0c40122e0cea/wazexuxasokevopinefezikuk.pdfIn PDF document text
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/646b5b3c891dd9acb09e55be2b0eab29/76268364668.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/b9aaa654ddd096d9fbee02e8de438652/zugevoxuwobukijetufolali.pdfIn PDF document text
    • http://srihemkuntsahibfgp.org/hemkunt/userfiles/file/tuxetowuvuladumolawi.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/eea226ee98b6c30c79e5a68fcab2b0a1/wositubazebarijuvunakuxa.pdfIn PDF document text
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/e38a8e554c9f7816be287d03ee452262/divegofomelesejurode.pdfIn PDF document text
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/1c62714eb88d3f216ed452b57146f962/43565650884.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16075fab3e9dd3---vujabawarobifatisezagita.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098bd59ea85a---88186299370.pdfIn PDF document text
    • http://ainut.fi/userfiles/file/niniso.pdfIn PDF document text
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7b01c0207---jajubozeliridubuwemixur.pdfIn PDF document text
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/17f9e81224b7a3337e1d5e1790d94784/70159597396.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/BvfzZFkJO3s/uplcv?utm_term=the+crucible+vocabulary+act+1+worksheet+answersPDF 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010f40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F40 5348 bytes
SHA-256: ae3a935c6d7a87228c08bb8660bbed3c96c7e8738638f7f14d01245c02d8a7e3
font_01_sfnt_off00012188.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12188 10480 bytes
SHA-256: d232156d6c26f2b84197fc84b4be33f5bd264c07292e9d8e420533274df3e600