Malicious PDF — malware analysis report

Static analysis result for SHA-256 b532dbf1997bcf25…

MALICIOUS

PDF

70.9 KB Created: 2021-09-03 11:10:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 6259f35f406348ac99303dbd9a3f853b SHA-1: 0c7656461400fca6b39e9bad1ef164543f3362b8 SHA-256: b532dbf1997bcf2579c0a08a4fec268e31102b3addfaa57a7e41128aea057cc4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm with numerous URLs pointing to compromised WordPress sites and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://kaparatt.com/images/File/42150203273.pdf In PDF document text
    • http://arci-mp.fr/admin/File/28370126245.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/637mii9p9h90qlefr9rj5cn995/varunijupuwajimunolajela.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079f32dd3f2b---61830392267.pdfIn PDF document text
    • http://vngo-cc.vn/cooker/public/files/47928006607.pdfIn PDF document text
    • https://mimpishio.com/contents/files/figekufonenogepig.pdfIn PDF document text
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/8df27a497cb782edb18cb3c8bec439c0/56799904918.pdfIn PDF document text
    • http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/7iba4l2ml77sitraejftaehl0d/42054196660.pdfIn PDF document text
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/7goi3se777uae8e9tn8nfo4t8v/nenon.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/eok3uhcd2iva0a9f2qg3vhkfls/guragok.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160a4674c61cf9---62529465388.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/160789812a5c41---lukibarusuregununi.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/senelum.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087ab8c61adb---57516715527.pdfIn PDF document text
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/f271bf8303f8ba484cef28062dd8e7c0/58367462246.pdfIn PDF document text
    • https://thietbidiensino.vn/media/ftp/file/44987451949.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/2nm3oq3cqtg05tlhafgj9b16o3/ribowajugokalifafupas.pdfIn PDF document text
    • https://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/8a7d9754945e4bc7307fe435a6c72d8f/38993835320.pdfIn PDF document text
    • http://mobilni-kadernictvi.cz/files/file/pezovukavudumibixagus.pdfIn PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/i639am87m8a2i2ug5331b3ig4g/81419865078.pdfIn PDF document text
    • http://studiosaletta.it/userfiles/files/49910815644.pdfIn PDF document text
    • https://sdhouse.info/ckfinder/userfiles/files/70544522120.pdfIn PDF document text
    • http://tolaniprojects.com/userfiles/file/xofojomop.pdfIn PDF document text
    • http://bukvoznaika.ru/ckfinder/userfiles/files/45040297028.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=necesidades+nutricionales+en+el+embarazo+pdfPDF 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_off0000b718.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB718 14924 bytes
SHA-256: 50598e3fc0a7c389c1cda862d6d7ab58a4b8c5d33a1033c909e44f7cf3f105aa
font_01_sfnt_off0000dbfc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBFC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f413.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF413 11060 bytes
SHA-256: 9bbbc0237ddbfc4dab72194a175bc2e3b367c57bece3b3ad16dc329d4982af8a