Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8159d78b17a64fc…

MALICIOUS

PDF

80.5 KB Created: 2021-09-18 15:31:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 9e60ec6caa7a398a19aeaa801d94679c SHA-1: e2c1a86a7a02f7374cd3f7636e34962ef6d3aefa SHA-256: a8159d78b17a64fcb90f641a83522487d92af7aab04cb790b411a5edde7a4f3a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The document functions as a link farm, with numerous embedded URLs pointing to various websites, including those hosted on compromised CMS platforms. The presence of these links suggests an attempt to lure users to potentially malicious sites for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 https://cructi.ru/uplcv?utm_term=sites+where+to+download+free+movies PDF link annotation
    • https://tselectromechanical.com/uploads/CKfiles/files/14348200903.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/7jkrt4ctpvlt2c8tokdlu2n2a9/fasixageb.pdfIn PDF document text
    • http://gimhaejazz.com/fckeditor/userfiles/image/mujadisafo.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/5jeml9fsqe7m7vao4vbf5o5ro4/18893724988.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1612f274a15561---vusuwoxugetupodixaf.pdfIn PDF document text
    • http://linhkienhunganh.vn/luutru/files/doviwexox.pdfIn PDF document text
    • http://bodemveenweiden.nl/bodem-veenweiden-img/77754759528.pdfIn PDF document text
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/1b1ca6507259794a7d56f3a822c1a8f0/41254238886.pdfIn PDF document text
    • http://xhzhengli.com/upload/14018406283.pdfIn PDF document text
    • https://cobaltinc.org/userfiles/file/29517825896.pdfIn PDF document text
    • https://aymfly.com/aym_image/files/zulimaxupebotox.pdfIn PDF document text
    • http://zhouzhuank.com/v15/Upload/file/202191315477853.pdfIn PDF document text
    • http://naoshima-habitant.com/images/blog/file/vafokevuwugar.pdfIn PDF document text
    • https://greenvalleykerala.com/ckfinder/userfiles/files/zuribosezawawogapudirener.pdfIn PDF document text
    • http://actlogistic.vn/upload/editor/files/gerikilibeximani.pdfIn PDF document text
    • http://skomi.ru/img/files/file/wumuxegilubuzis.pdfIn PDF document text
    • https://megatex.ua/images/uploads/file/75443126853.pdfIn PDF document text
    • http://myxroad.net/upload/userfiles/file///tosorogojofimo.pdfIn PDF document text
    • http://yaan121.com/uploads/files/202109110201414406.pdfIn PDF document text
    • http://aesg2edcv.handylover.com/upload/files/12985028372.pdfIn PDF document text
    • http://tznjl.com/userfiles/files/virakeduranip.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_off0000d5f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5F8 17348 bytes
SHA-256: 0f7a14c96233ef603fa3e0a9bb6294f3f354700dd126f36c7697e09ed8f94989
font_01_sfnt_off00010316.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10316 10848 bytes
SHA-256: 3813e7d7d797f562ff566ab9747b3a83ce6dd6c753a4b8da05877983ea1961f3
font_02_sfnt_off00011bfc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BFC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1