Malicious PDF — malware analysis report

Static analysis result for SHA-256 85a3f0fb6c4c1a3a…

MALICIOUS

PDF

81.4 KB Created: 2021-09-11 06:28:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: b4676a6e6387eb8e1a49ff98bac9e7ad SHA-1: d30fa973dc208587eab9454f29384e5d8f74e316 SHA-256: 85a3f0fb6c4c1a3a76d3c2dee4cbfa59e517f4d34bbf5c7a5bb51a3db133d200
156 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many of which point to compromised websites or use disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. No scripts were extracted, and the document body was unreadable, but the link farm behavior is sufficient to classify it as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 http://projecthouse.bg/uploads/CKfinder/files/97262723565.pdf In PDF document text
    • http://vimbark.sk/editor_uploads/files/kuvowuxip.pdfIn PDF document text
    • https://taksis.lv/taksis/userfiles/file/zoxupadigupusato.pdfIn PDF document text
    • http://aow.infogestnet.it/ckfinder/userfiles/files/zelositaxubifisozuzuvufud.pdfIn PDF document text
    • http://cl-metalparts.com/d/files/29959789580.pdfIn PDF document text
    • http://www.jysunshine-hotel.com/up_files/file/50379702774.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16135e59ad5442---15011978178.pdfIn PDF document text
    • http://seamacros.com/upload/file/tadodojezebudidipudiloso.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/d042d475112bdf52d472e9ac8300504f/35582408931.pdfIn PDF document text
    • https://bike-accessories.supersites.gr/content/ckfinder/files/62427388715.pdfIn PDF document text
    • http://backkwang.com/userData/board/file/17476032533.pdfIn PDF document text
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130a44b5812a---49466369228.pdfIn PDF document text
    • http://vector-mebel.ru/uploads/files/mejezisu.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/qpsp8m6uvspqbtrkn1b63dbkd5/99744909710.pdfIn PDF document text
    • https://noithatkuongthinh.com/uploads/files/linuwab.pdfIn PDF document text
    • https://nepalipublisher.com/ckfinder/userfiles/files/darupodepurelanabekivoxup.pdfIn PDF document text
    • https://pui-vital.ro/msg_media/file/51521922467.pdfIn PDF document text
    • http://lovesenergy.nl/file/3233806720.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/vd095lflf5334ja1hcuu382nj2/tiluxivarikufibatufafiwo.pdfIn PDF document text
    • https://booburger.myagenda.cz/pictures/editor/files/15774453138.pdfIn PDF document text
    • http://pxmonastery.org/CKEdit/upload/files/8318231882.pdfIn PDF document text
    • http://dienlanhhuubinh.com/upload/files/fofuwufasapulapofetoruj.pdfIn PDF document text
    • https://www.gurgy.net/ckfinder/userfiles/files/71215641187.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=holly+hagan+body+bible+pdf+downloadPDF link annotation
    • https://www.alamy.com/licenses-and-pricing/?v=1In PDF document text
    • https://www.alamy.com/hollyIn 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_off0000d5e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5E5 10740 bytes
SHA-256: 68e23038c87dbdc14c559d1a72c4bdb5d08909713e0f093e73c89ff5b65aa34e
font_01_sfnt_off0000ee15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE15 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010627.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10627 19152 bytes
SHA-256: 546d3cc9292f0d3d7e25b9c4759bc2c645842b2c9b74759a57309237ae5f079c