Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3e56e4a364f418e…

MALICIOUS

PDF

86.8 KB Created: 2021-07-14 06:16:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 607b0e2279372d66776ea9a0d5d158d2 SHA-1: 88b0569b084ce9f48c57c4dbf84d5b398ecbeb4a SHA-256: a3e56e4a364f418ee242bd63fdcfb8b445c51e0559322e64f5c7ee94ac3f0e52
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

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. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • 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.
  • 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://crewmak.ru/uplcv?utm_term=the+byrds+lay+down+your+weary+tune PDF link annotation
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/9950bb664197d54221d48d7ef02e9ed2/bonugosesuxeloku.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/13c250a3c0648c2ebf17e85a6f8cb7d0/valibisuwufez.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/9efb70e23f192024f15cb12c1cc0680d/nuxipemekatiwe.pdfIn PDF document text
    • http://osrclass1967.com/clients/8/84/84e84eb3bb32f45446e669e24fea3ebc/File/vululetisumek.pdfIn PDF document text
    • http://vankouwenenmastop.nl/UserFiles/file/85206523773.pdfIn PDF document text
    • http://burchiellati.com/file_fck/file/55093407903.pdfIn PDF document text
    • http://brilspa.ro/userfiles/file///33903570165.pdfIn PDF document text
    • https://biomedchita.ru/imeg_master/file/texogixiziguzo.pdfIn PDF document text
    • https://eyescare.vn/app/webroot/upload/ckfinder/files/baduxemaresixud.pdfIn PDF document text
    • http://tutaylamhet.com/storage/ckfinder/files/67168456145.pdfIn PDF document text
    • https://monuments-msk.ru/wp-content/plugins/super-forms/uploads/php/files/c0df1306da82d1e2ed4c48def8b88ac3/44535677156.pdfIn PDF document text
    • http://xnucleus.com/members//member_images/files/3017053248.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/itfk2t09714an4fh2ncspacee3/32342809061.pdfIn PDF document text
    • https://fidelishospice.com/ckfinder/userfiles/files/82604007157.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/601c7040d76827ddf1b754afad38c4b2/fulitexavikopumelake.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/aea9b1968a2602a1afca8daa1cfcbce3/88753982458.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b41b599875f---xasipuwunakimajowudok.pdfIn PDF document text
    • http://servis-hradec.cz/files/file/vavusisuxogawodu.pdfIn 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f0db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0DB 10656 bytes
SHA-256: d217d215bc4a9ce73f7eb21c6f44977e81b24d2464f76a8fa1d7b3ef5f2583e4
font_01_sfnt_off0001094f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1094F 16740 bytes
SHA-256: a2056ff4aa634a96a00d176ce21d9e5af032ce8baf27b5add10f2bedf8050c72
font_02_sfnt_off0001348b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1348B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1