Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1a86b6c3b53290c…

MALICIOUS

PDF

69.0 KB Created: 2021-09-27 02:49:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: d54b938a68a8b3aec1fa6f5f88b2b4af SHA-1: 78a52458a39cad0befc6ef24dcf9ad6bfea776da SHA-256: b1a86b6c3b53290c1e771c11ca2d22a0a9f78a28eefcffafe28acc1084dabfc7
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF is identified as a phishing lure due to its image-only nature and embedded clickable links. The heuristics indicate a link farm pointing to potentially compromised CMS upload storage and disposable hosting, suggesting an attempt to distribute malicious content or phish for credentials. The ClamAV detection and ML classifier further support its malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 69 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://allytemp.ru/uplcv?utm_term=kali+linux+nethunter+for+android+no+root PDF link annotation
    • http://udmvdpo.ru/images/files/zawixokowemeka.pdfIn PDF document text
    • https://hainutedecopii.eu/ckfinder/userfiles/files/9646886464.pdfIn PDF document text
    • http://mcutech.net/files/22613724722.pdfIn PDF document text
    • http://matsusushionline.com/uploads/files/vefudu.pdfIn PDF document text
    • http://c2ctrading.org/cms_upload/files/48056178333.pdfIn PDF document text
    • http://fandimnarodaku.cz/upload/file/saxepinojupuzezipapinape.pdfIn PDF document text
    • http://grgct.com/ckfinder/userfiles/files/71905292511.pdfIn PDF document text
    • https://www.nitm.ac.in/nitmeghalaya/ckfinder/userfiles/files/fedakoji.pdfIn PDF document text
    • http://millecolori.it/images/file/34313000855.pdfIn PDF document text
    • https://bunianco.com/other_files/File/26302449858.pdfIn PDF document text
    • http://isystemlab.com/admin/ckfinder/userfiles/files/67230122355.pdfIn PDF document text
    • https://wwa.bdbabymart.com/app/webroot/ckfinder/userfiles/files/51067563641.pdfIn PDF document text
    • https://firsatoyun.com/calisma2/files/uploads/tivulifelilisozerozobepo.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16150f1b581948---65066371490.pdfIn PDF document text
    • http://boatmonies.com/uploads/files/derunexobitukema.pdfIn PDF document text
    • https://doanhnghiepvietnam.niengiamdoanhnghiep.vn/img_duhoc/files/40196777596.pdfIn PDF document text
    • https://rumahbaruku.com/contents/files/95652902064.pdfIn PDF document text
    • http://metisentry.net/ckfinder/userfiles/files/fesagi.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/420de3c236c0e753f76e982a85ee7d18/xiromezurusa.pdfIn PDF document text
    • http://gattoneva.pl/pages/userfiles/file/sapap.pdfIn PDF document text
    • http://montpellier-business-plan.fr/mbp/upload/images/images/upload/ckfinder/kegorivalegizuwawusa.pdfIn PDF document text
    • https://buffinvestment.com/upload/ckfinder/files/kesumu.pdfIn PDF document text
    • http://antifftech.com/uploadfile/file///2021090614444772.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/e619857a0be8fd9ba879d26674655365/45227970026.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/6c5c1192c0c98c84936afc7422983501/29497042210.pdfIn 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_off0000b391.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB391 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cba8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBA8 10476 bytes
SHA-256: 361f92a021f372087b6ff1ba0296c7608e8c98b01a3a0388269802aee973a11e
font_02_sfnt_off0000e35c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE35C 13880 bytes
SHA-256: cd0d91ea030eb87f74ae4354bcd740f883d904cb140be7c5f339193e1279622d