Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f37c42a7a458911…

MALICIOUS

PDF

81.3 KB Created: 2021-09-05 21:16:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 91b03f93acf5ba864b17258ba9fa6cf1 SHA-1: 84620608e0abafafcae82cd5a14b0f08c5ecd2ae SHA-256: 5f37c42a7a45891197dd9e4fa0d9829806b3d93dfe54eb390200655de8941448
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, suggesting a link farm or phishing lure. The ClamAV detection and ML classifier strongly indicate malicious intent. While no scripts were extracted, the structure and URL patterns are consistent with SEO poisoning or phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://rainbowfurnitures.com/files/files/dexos.pdf In PDF document text
    • http://nikacarpet.com/My_Project/Hamishe_bahar/ahar_img/files/67060717695.pdfIn PDF document text
    • https://ceccarmaramures.ro/userfiles/file/84748461887.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/161052c1014c5f---refologopezubakuzat.pdfIn PDF document text
    • http://www.shjkyq.com/up_files/FCK/file/40261546726.pdfIn PDF document text
    • http://lltsg.com/uploadfile/file///2021072617414968.pdfIn PDF document text
    • http://bocghebinhduong.com/media/ftp/file/10196821849.pdfIn PDF document text
    • http://judge1960reunion.com/clients/873273/File/lifufosizela.pdfIn PDF document text
    • http://strandedtattoo.net/file/lodukudojizenozadilepoza.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1606f0eb83a867---17085738550.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/o68qn99gjiovjqop4ttqdjeioe/busorojogegip.pdfIn PDF document text
    • http://szyqjsj.com/UploadFile/file/20210823162406030.pdfIn PDF document text
    • http://asbufestival.com/uploads/FCK_files/file/gorunilopatepidog.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/grh6j6ink6ch3pibentcjpvh29/rolizakibamuzago.pdfIn PDF document text
    • http://turnwealthy.com/ckfinder/userfiles/files/22915084395.pdfIn PDF document text
    • http://p-itos.net/admin/userfile/image/file/tabagaxivigefimavupofopap.pdfIn PDF document text
    • http://polletnv.be/uploads/files/10489046535.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/kenorimuxakoliki.pdfIn PDF document text
    • http://kalmi.ru/upfiles/files/23249355174.pdfIn PDF document text
    • https://warsztatgdynia.pl/app/webroot/media/files/sulejoxezojido.pdfIn PDF document text
    • https://blugarden.eu/file/tajakikarinudujodivi.pdfIn PDF document text
    • https://hospvetcentral.pt/site/upload/file/75688644858.pdfIn PDF document text
    • https://www.breastcancerfoundation.in/wp-content/plugins/super-forms/uploads/php/files/5b235046e15b541df97a5f79ceb0f66e/51115245713.pdfIn PDF document text
    • https://www.rydalmereprestige.com.au/wp-content/plugins/super-forms/uploads/php/files/ketadl0r1sb5bm675i7jo70ov9/gepadoziwakunofawutimoz.pdfIn PDF document text
    • http://conelser.hu/fck_uploads/file/jegulozurumexufopasab.pdfIn PDF document text
    • http://harringtonassociateslaw.com/Test/JabzMedicalBillingService/userfiles/file/40912885367.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=rx8+service+manual+pdf+downloadPDF 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_off0000d612.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD612 11288 bytes
SHA-256: 0a8a350e0160793839334d312522a08d2f6aab7fcd1ce65198e4523cec410494
font_01_sfnt_off0000f0a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0A9 18312 bytes
SHA-256: 9dd90c77c17c9c20b28f6e55fef257f44e59820b3e62a9285c22a29fa70a51ef
font_02_sfnt_off00011fec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FEC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1