Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6fb4bcd2b7fab80…

MALICIOUS

PDF

77.8 KB Created: 2021-07-04 10:07:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 729fe5cf4506b99a0af1638288677d72 SHA-1: 314feb8966fb546571d0e1181b8a57ef6fcc536d SHA-256: a6fb4bcd2b7fab80db10b81f7f7f0abf7e8212d049c8c99fff4397fbb8c634a5
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 0.9953

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://cructi.ru/uplcv?utm_term=principles+of+biostatistics+answers PDF link annotation
    • http://busankid.com/webfiles/board/file///womole.pdfIn PDF document text
    • https://www.enterpriselighting.com/wp-content/plugins/super-forms/uploads/php/files/acdbed4a11fd72d96eb35c156abe0fea/18033732386.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/81821097926.pdfIn PDF document text
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/38775cdfde9e9075a4624ca1364b4626/rekotovemet.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/16081a7b50f27b---kejegikagovewojeti.pdfIn PDF document text
    • http://www.siscbolivia.com/admin/uploaded/fck/file/paralopumexafitojebimowig.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160cfce1a1c6c7---tobisapesinalara.pdfIn PDF document text
    • https://designcoordinators.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e991b284d7---rajegedegazaxuji.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca705d7ed6---77395443987.pdfIn PDF document text
    • http://aihyang.com/userfiles/file/nuvupitixesatuba.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608653caf1856---93782791509.pdfIn PDF document text
    • http://wksx.top/images/userfiles/file/giviluxilawodalor.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/e2b5a581e184a48804c8670b94e9332e/vubanimafivo.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/4g8ngk8etahmtacfi50a1ocut3/zetiwavuwetabijaruki.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce05d41947---suterufegeripa.pdfIn PDF document text
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/ea7bb9846b446b49198a3979da0a4a8a/83353941080.pdfIn PDF document text
    • http://fullcolorspandoeken.nl/userfiles/file/pawuwodumekuvalujabifebox.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/7rf23nfkj0beuhfh2r3mhcuc58/japojegogowusuw.pdfIn PDF document text
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/0b4a35288d3f078f4a89430462c0a942/9435225005.pdfIn PDF document text
    • https://advantagelic.com/singhania/downloads/file/29758253967.pdfIn PDF document text
    • https://travelinnsuites.com/nbloom/fckuploads/file/36523763622.pdfIn PDF document text
    • http://buergerforum-tirol.at/file/benozajoxima.pdfIn PDF document text
    • http://thedreams.cz/files/5453214953.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_off0000cfcf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFCF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e7e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7E1 16120 bytes
SHA-256: 6178f51c14b98b9c5b46cb7489c3a79b776a5412d84cebf188175021511eb6b7
font_02_sfnt_off000111a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111A7 10700 bytes
SHA-256: a061784c49628eb5f2c23d39bff1a455972cf3a2ade67c2e3cf6e255878df808