Malicious PDF — malware analysis report

Static analysis result for SHA-256 4225a794297c5b95…

MALICIOUS

PDF

91.6 KB Created: 2021-08-04 00:27:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 2ce84ad56c3314552b85db75e8820fdd SHA-1: 43bbb398a7cdd0b6d398d515525b2b1f3aa712fb SHA-256: 4225a794297c5b9576fa708888fd0f81cb7b60d3a4677c3257ae35f48a50fd85
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV detecting it as a phishing trojan. It contains numerous links pointing to compromised WordPress sites and disposable hosting, suggesting it's part of a link farm designed to redirect users to malicious content. The primary attack pattern involves luring users to these compromised sites, likely for phishing or to download further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 https://laborke.ru/uplcv?utm_term=how+to+report+employee+theft+to+police+uk PDF link annotation
    • http://ecompletecontact.com/ckfinder/userfiles/files/dokapenusawidak.pdfIn PDF document text
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/oqasu5sifb3ts502cn5pqhsl04/vaxosepoleso.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ab95d3ae4f9---30488652072.pdfIn PDF document text
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/76628t9q6rcb2hc8rnd5qe9cj0/xopusovo.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1606fbb59186bd---89477890157.pdfIn PDF document text
    • http://harchovyk.com/userfiles/file/morevadepavowarum.pdfIn PDF document text
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/epric6jlphfc8fpjeotk33cup2/jikozapunipeluvumojis.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/5912674a774ecc8b1e81a9e79d259141/14794725673.pdfIn PDF document text
    • https://orsolyajuhasz.com/ckfinder/userfiles/files/54687871560.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad1c7f75517---javugebapufavuwasufar.pdfIn PDF document text
    • http://accessiblevehicleservices.com/userfiles/file/66802696269.pdfIn PDF document text
    • http://dmkaudit.sk/101/upload/file/vediwab.pdfIn PDF document text
    • https://gdr.co.il/wp-content/plugins/super-forms/uploads/php/files/f2237be96aa3929caa96ea3ce4a64130/28939831401.pdfIn PDF document text
    • http://aryajob.com/user_upload/file/82062448768.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/1609ab80610691---xosimiloxaw.pdfIn PDF document text
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f30c93cebb---zaxuwagawotogedisudujow.pdfIn PDF document text
    • https://alkalacarservice.com/public_html/userfiles/file/88771567958.pdfIn PDF document text
    • http://rspon.pl/images/wyswig_images/file/74264725082.pdfIn PDF document text
    • https://almondzwealth.com/administrator/imagetemp/file/tusejofelugifaxada.pdfIn PDF document text
    • http://homenet-spb.ru/userfiles/file/bofazejozosawututukuvopa.pdfIn PDF document text
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/97206fe244c693ec719c6dcc84d0af16/tufevudo.pdfIn PDF document text
    • http://ck-kutnahora.cz/gais/image/file/17980805270.pdfIn PDF document text
    • http://shop-cartuning.pl/userfiles/file/49611672407.pdfIn PDF document text
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/rnjp5f3972e83rs429dtabmu63/toxegeliwekitijevukutimo.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_off0001035c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1035C 16696 bytes
SHA-256: e26d74b9730bf1c94aaf760e52560f951b5603ac3e47a2a7af43e83b0a114ca5
font_01_sfnt_off00012eb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EB0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000146c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x146C7 10696 bytes
SHA-256: 9abe5219842148f2aaf6c15433aa7eec1cfbd56a5722c0ee6ce5e2f9875e8f6f