Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c63838b2a3bca37…

MALICIOUS

PDF

68.8 KB Created: 2021-09-27 11:20:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: d464762eb8b9bff35dc9d63138033462 SHA-1: d28d5adb47f5b1c6823f1ab7b5793ef6c549827f SHA-256: 5c63838b2a3bca37563452d64ae800248f98a31733a7f02ff9ae50a6c53b864d
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm pointing to various PDF files hosted on disposable domains, likely intended to trick users into downloading further malicious content. The presence of multiple external URIs and link farm heuristics strongly suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://irodaszer.lukinserv.hu/file/27895798566.pdf In PDF document text
    • http://www.advokat.com/app/webroot/img/fck/file/sebusesedaw.pdfIn PDF document text
    • http://chanakol.com/ckfinder/userfiles/files/jigonumogupopizilusojogit.pdfIn PDF document text
    • http://ldkxzzs.com/images/userfiles/file/musoxog.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614080afa98d0---6988811721.pdfIn PDF document text
    • http://bfcy88.com/uploads/files/donemaj.pdfIn PDF document text
    • http://nwhouse.ru/uploads/file/49238587966.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135930f02705---8664931725.pdfIn PDF document text
    • http://nuklearmedizin-amro.de/userfiles/file/44144811136.pdfIn PDF document text
    • http://ccsup.co.th/uploads/ckfinder/files/pizibunakoxezototili.pdfIn PDF document text
    • http://szcftz.com/upload/pelonubuvurugirume.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/oadfrbf99i7fali1l4jjnvslj7/40554480657.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/08b30b01149ea95d198a477153674f04/xisar.pdfIn PDF document text
    • http://vipnjl.com/userfiles/files/logot.pdfIn PDF document text
    • https://hophamthaibinh.com/upload/files/zutenisumemosevo.pdfIn PDF document text
    • http://placidlakes.com/larpm/uploads/file/nuvuvumufotifirovifita.pdfIn PDF document text
    • https://aluminiosarla.com/userfiles_arla/files/wisol.pdfIn PDF document text
    • http://aardbeienfeesten.nl/uploadimages/files/nexazusonurudafokek.pdfIn PDF document text
    • http://sourceandsecure.com/uploads/userfiles/file/regawalivodovizofur.pdfIn PDF document text
    • http://vallovin.it/userfiles/files/22805759911.pdfIn PDF document text
    • http://www.hebrewforreadingcomprehension.com/content/67116741020.pdfIn PDF document text
    • https://saint-florentin.charcutier-traiteur.fr/ckfinder/userfiles/files/46557582524.pdfIn PDF document text
    • https://gonguyenkhoi.vn/upload/files/69481987810.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/161405d0a8dc08---74739889144.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=football+strike+apk+downloadPDF 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_off0000afb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFB5 14912 bytes
SHA-256: f6fbe4bc00926d897c73948c64827460382d06c3a4a90bc9c545d202cce735c9
font_01_sfnt_off0000d54f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD54F 10680 bytes
SHA-256: 1251766d769435b74d81845e1d44e73e7f32860392735e5ab8c15c5b64303aa9
font_02_sfnt_off0000edc3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDC3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1