Malicious PDF — malware analysis report

Static analysis result for SHA-256 f16b9d3cefc43344…

MALICIOUS

PDF

89.7 KB Created: 2021-06-30 17:42:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 14351935d68d2e6a7ff4271050b9816d SHA-1: bdb88db0496c690cbb5b13933d01d3a8e451d2c5 SHA-256: f16b9d3cefc4334413512dc0699eea1fa5a87d3b10ff3e7efce3eed3c2e46fa0
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Numerous heuristics point to the PDF acting as a link farm, directing users to compromised websites and potentially disposable hosting. The embedded URLs suggest a phishing or malware distribution scheme, leveraging compromised CMS uploads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/3b8579089e0aac955d774da50ef53106/12087238649.pdf In PDF document text
    • https://edu-mate.kr/_UploadFile/Images/file/nofapivuvonis.pdfIn PDF document text
    • https://concertwristband.com/resimler/files/matijaroseb.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cbfcc457bc6---kokenato.pdfIn PDF document text
    • https://www.scilights.com/wp-content/plugins/super-forms/uploads/php/files/03732a138aa6be6a2f5841aeb68f32f9/77415523329.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a060af030b5---zobajujapikig.pdfIn PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16077b1181695b---98192275814.pdfIn PDF document text
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/qnmr93158eadtok8l1al7r3rud/5329887597.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c6f5572ab81---82243672175.pdfIn PDF document text
    • https://canvasations.com/wp-content/plugins/super-forms/uploads/php/files/lsdejqka76af84ke5g1qo4q5e1/95918526987.pdfIn PDF document text
    • https://aihr-iadh.org/uploads/FCK_files/file/78751166968.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090e2e743b7f---60642451251.pdfIn PDF document text
    • http://studiocalderini.it/userfiles/files/ketirumusis.pdfIn PDF document text
    • http://www.anclupnapoli.it/userfiles/file/20448850694.pdfIn PDF document text
    • https://outsourcedbackoffice.co.uk/wp-content/plugins/super-forms/uploads/php/files/867b9627b8396afbdec1054cce6a845b/jaruxigiwojeturemekokoxa.pdfIn PDF document text
    • https://mallncart.com/userfiles/files/tefewukisekunuf.pdfIn PDF document text
    • http://hy-concrete.ru/d/files/79829860950.pdfIn PDF document text
    • http://amsasecretariat.fr/userfiles/file/57294276956.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a65d62a14f8---79572285029.pdfIn PDF document text
    • https://realestateconnect.us/wp-content/plugins/super-forms/uploads/php/files/7ia091qt3n4hcmfbp5b956ukm4/99079810405.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/v5aet2og1566k25fd7ahutq9t4/10024179959.pdfIn PDF document text
    • https://chaplains-camps.org/upload_picture/file/vefifuwikokobegozibofeg.pdfIn PDF document text
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/87135847294.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/1607eddef2fe00---zupikemurekomuzupogi.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/4ee279d836445e0213e91610b7a19ea0/68345097002.pdfIn PDF document text
    • https://pinpointfeedtech.com/ckfinder/userfiles/files/69535416074.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=regret+email+to+candidate+after+interviewPDF 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_off0000f9bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9BF 17608 bytes
SHA-256: 26ed5641e7fed87fa84339265b7dac66a0899864ac1221c4d89b6f3ea2ad4cfe
font_01_sfnt_off0001284a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1284A 10848 bytes
SHA-256: 27e0678627d91deb7fb5adc0fc127b0e2216f33ccc3fd2002c1f90107d317042
font_02_sfnt_off0001412d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1412D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1