Malicious PDF — malware analysis report

Static analysis result for SHA-256 c76b8dd432da684d…

MALICIOUS

PDF

116.8 KB Created: 2021-07-22 21:29:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: a538eaac991d2ccfeff100a395422855 SHA-1: 665b9b8ffa998f57aed92f76da807d6b05f60558 SHA-256: c76b8dd432da684dab04b3568181c78c836fc20500c87979a33e002cb8e156bb
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged as malicious by an ML classifier and contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document's primary purpose is to act as a link farm. While no scripts were explicitly extracted, the presence of embedded URLs suggests an attempt to redirect users to potentially malicious sites, aligning with spearphishing attachment tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9967

Heuristics 5

  • 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://fullhousetourism.com/UploadFiles/file/20210520231349149.pdf In PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b81b69290bb---96944477468.pdfIn PDF document text
    • http://boxethai38.comupload/file/29674086856.pdfIn PDF document text
    • https://zweiund40.com/wp-content/plugins/super-forms/uploads/php/files/5vroqfk9j1ncvq6ls2ckooq1v5/65666451033.pdfIn PDF document text
    • http://letsbelegal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gopozibumivefubip.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/dscqoh6ngiivqt0g9d5gpia7k7/loxadosagaxadaranole.pdfIn PDF document text
    • https://adsbudget.net/userfiles/file/jumefasopewafuwowekazed.pdfIn PDF document text
    • https://bishopsalamatkhokhar.org/userfiles/file/64958136699.pdfIn PDF document text
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/7aff0e5bcfa574d15752dc9757daaa69/bamizakowogonojomob.pdfIn PDF document text
    • http://coimbra.hu/uploads/ckfinder/userfiles/files/kodumepugakujodovoponu.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/2ac1b1b2f57d40930b75c6b39a71e02c/vejopufapepibato.pdfIn PDF document text
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/a80655777c4f9b0826b7c91f826acfd5/86199524851.pdfIn PDF document text
    • https://villatoscana-pi.it/userfiles/file/48511313872.pdfIn PDF document text
    • http://padgettlawreunion.com/clients/79772/File/jifozovovotugolexirede.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d9ab643df9a---80393516943.pdfIn PDF document text
    • http://www.magicapro.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c10205c1887---bepodekubaw.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7fa1af101---muroguri.pdfIn PDF document text
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d09aeab090---jadatof.pdfIn PDF document text
    • https://observatoire-omic.org/documents/file/7483152576.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/1ptbfh2qod76u7n9vfo0d22uq0/83631315589.pdfIn PDF document text
    • http://vngo-cc.vn/cooker/public/files/65340188809.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c5d43e1810---lutotemodufoj.pdfIn PDF document text
    • http://clinicoral.com/img/userfiles/files/temumuma.pdfIn PDF document text
    • http://446888.top/userfiles/file/64921089730.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=bruner+and+scaffoldingPDF 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_off0001673b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1673B 17140 bytes
SHA-256: 4151f2201f9aa1a927579da03169454ff0e32d0c37107c4458ac109141de5e18
font_01_sfnt_off000193f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x193F4 10708 bytes
SHA-256: a21da14451fd025fad596f70cb3a29701ca3a9b4444713f446311f12321d8855
font_02_sfnt_off0001ac6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1AC6A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1