Malicious PDF — malware analysis report

Static analysis result for SHA-256 4377d6c381d8a625…

MALICIOUS

PDF

88.4 KB Created: 2021-06-30 05:12:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: f29af7756d77d389eb3bcb594f0ced5a SHA-1: ceeeed8000743437965160d1f98ec3354e16cace SHA-256: 4377d6c381d8a62571a299028c2c8d82a62668738a3b8e6806d7897a8d1b65a6
156 Risk Score

Malware Insights

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

The sample is a PDF file that exhibits characteristics of a phishing lure, specifically referencing 'irs estimated taxes 2021' in one of its URLs. The presence of numerous links pointing to compromised CMS upload storage and disposable hosting suggests an attempt to distribute malicious content. ClamAV detection as 'Pdf.Phishing.Trojan' further supports its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1606dcf7870454---vukulom.pdf In PDF document text
    • https://beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/3eda465677ca8e829aa0fdfea1522b1d/43441920703.pdfIn PDF document text
    • https://altinhediyeler.com/calisma2/files/uploads/53670406961.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b16cddad1a6---kupamoxofiwotaguni.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160721aed60e68---wikumowunuviwiw.pdfIn PDF document text
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/b4f2efbe809119e0e158ce003622f371/78356585083.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/c065fdf6222c2d5a8f0a26303c6d153d/sowufi.pdfIn PDF document text
    • http://preserveproperties.com/userfiles/files/zonukuzapuwug.pdfIn PDF document text
    • https://go2germany.ru/files/file/64810750676.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/sfb2sohr9c8ohfikdfpbj7vt8a/48688657922.pdfIn PDF document text
    • http://danburyhighclassof1961.com/clients/b/b4/b42d7d7907ff1a67dd6fd366dd3c6775/File/matezo.pdfIn PDF document text
    • https://lea-inc.com/wp-content/plugins/super-forms/uploads/php/files/054aa33d821a890bdae942a0e4478432/lupisifo.pdfIn PDF document text
    • https://binarbaidequipment.com/public_html/userfiles/file/69565262911.pdfIn PDF document text
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160ae11da2b827---nedimebabukakusi.pdfIn PDF document text
    • http://atdawnwelift.com/userfiles/file/77364926465.pdfIn PDF document text
    • https://xanbiente.de/userfiles/file/sosunom.pdfIn PDF document text
    • https://archltginc.com/wp-content/plugins/super-forms/uploads/php/files/afd50cc2e34feba63fa64f0e9605ad59/88476687322.pdfIn PDF document text
    • http://www.odnpoznan.pl/fotki/file/file/vedidasusegaxadefepuxetef.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1609d0ccb8f89b---40323326467.pdfIn PDF document text
    • http://bestorkate.com/uploads/ckeditor/files/28520355670.pdfIn PDF document text
    • http://prestopc.it/upload/file/wejakakekiwobesop.pdfIn PDF document text
    • https://www.northwoodmedical.ca/wp-content/plugins/super-forms/uploads/php/files/b9sapedb8bvfm9c0ovji3k4mfe/vogibuwugetivakazigujebul.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608d6e6478335---54488505619.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adc39220f0c---12224910636.pdfIn PDF document text
    • https://citronixdeflection.com/nbloom/fckuploads/file/33678996248.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=irs+estimated+taxes+2021PDF 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://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_off0000f6f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6F6 10484 bytes
SHA-256: 4c1a8b1628b22e73ed0935d19b9435947e59d81e205d9b2fb7ab1fbce0710135
font_01_sfnt_off00010ef3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EF3 17304 bytes
SHA-256: 587212c022f70dcb2c1c58caee28814cb4c536780d4f7091a8a94c382ff948d8
font_02_sfnt_off00013c69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C69 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1