Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b8a4bdf8b8e973f…

MALICIOUS

PDF

79.1 KB Created: 2021-08-31 08:49:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 9a0867fcaf2317750bf6f744e627b1c6 SHA-1: 7f81855a47f43032ade15de16b7a3be536fa8d7a SHA-256: 1b8a4bdf8b8e973f2dcd83b537135941e63150398e6dde004ca2797de255a233
156 Risk Score

Malware Insights

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

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. The heuristics reveal that the document functions as a link farm, directing users to multiple compromised websites and potentially disposable hosting domains. These links are likely intended to facilitate phishing attacks or distribute further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160a7164262655---92966719682.pdf In PDF document text
    • http://dui-antidote.com/images/userfiles/file/21160344061.pdfIn PDF document text
    • https://precisionautoandac.com/wp-content/plugins/super-forms/uploads/php/files/977bbdfd09ddadf0317a3856070464b5/1460442252.pdfIn PDF document text
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/gfiilgaiie0pn4l4da6hpapmvr/pusejusadagaselufum.pdfIn PDF document text
    • http://shophouse.info/images/files/birijaledivol.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607b2a8ac22b8---morezeveturuwerum.pdfIn PDF document text
    • https://tumsad.org/img/editor/image/file/durawix.pdfIn PDF document text
    • http://sieuthikhoacaocap.vn/upload/files/93668860294.pdfIn PDF document text
    • http://plkorea77.com/ckupload/files/vipokifakudadikopuvojiwek.pdfIn PDF document text
    • http://logenamerica.com/userfiles/file/zapofoxu.pdfIn PDF document text
    • http://taociren.com/upload/file/210818121446375001mcobmdnd8ljc.pdfIn PDF document text
    • http://tw-sincere.com/upfiles/editor/files/50169920255.pdfIn PDF document text
    • https://mehreganimaging.ir/images/upload/files/vukodikega.pdfIn PDF document text
    • http://angelcabrera.com/FCKfiles/file/27525396737.pdfIn PDF document text
    • http://dominoliberec.eu/images/file/files/12760018622.pdfIn PDF document text
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/2b99868b64d7e016688d7292f04a8ef6/vekabaw.pdfIn PDF document text
    • https://cleanenergy.mn/uploads/files/17223685384.pdfIn PDF document text
    • https://marblo.ph/app/webroot/img/files/4484781562.pdfIn PDF document text
    • https://baglab.pl/galeria/file/lupufebuxogif.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160a062f575729---jomagakizotak.pdfIn PDF document text
    • http://ibtaker.ps/userfiles/file/44373510213.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606d49d28d084---donupimotukilemupiwow.pdfIn PDF document text
    • http://chinalabware.net/d/files/59855476620.pdfIn PDF document text
    • http://uss100.com/clients/5/56/562308f4da1da23328cfd9e5c9f3e68f/File/34335033819.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=made+4+cleaningPDF 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_off0000d41e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD41E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC30 17108 bytes
SHA-256: bf43a8e68a246ddbb69e0c89ab2a4ac4d62b5ba12fa39af50121e183a3de7371
font_02_sfnt_off00011877.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11877 10132 bytes
SHA-256: ac0e0fae6e82538385e5f58e9c99d476e6a3d802fddc9056846b712d500083d9