Malicious PDF — malware analysis report

Static analysis result for SHA-256 51d062d834d64fca…

MALICIOUS

PDF

81.0 KB Created: 2021-08-23 17:48:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 54454435cf2371585e969be57d47601e SHA-1: d9f71fe33c564041d17d2527a39a579a2991e269 SHA-256: 51d062d834d64fca3c0dfb78fc50b893db12c897fdf88edc60a79c4079918178
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of external links, many of which point to compromised websites or disposable hosting, indicating a link farm for SEO poisoning or phishing. The ML classifier strongly flagged this PDF as malicious. No scripts were extracted, but the presence of numerous URLs suggests an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 5

  • 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://huntic.ru/uplcv?utm_term=fettuccine+alfredo+with+shrimp+and+mushrooms PDF link annotation
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160acc10311a31---velevesezifalejenadojibeb.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/160b5d79d870ac---vixegurudetewaj.pdfIn PDF document text
    • https://autotrans911.com/thread/admin/uploads/file/likolupinon.pdfIn PDF document text
    • http://pngroup.pl/ckfinder/userfiles/files/welapokiwebizopopovavor.pdfIn PDF document text
    • https://www.mnspineandsport.com/wp-content/plugins/super-forms/uploads/php/files/fbaf7b514978f81d32c53277977433b3/panedaxojedu.pdfIn PDF document text
    • https://araprinter.com/ckfinder/userfiles/files/zoripepowiz.pdfIn PDF document text
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/0f6a540aa966a6376119e3206d378930/16007999547.pdfIn PDF document text
    • https://htddienstverlening.nl/userfiles/file/21395141113.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612155d3d83a7---99582154789.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160db94518a819---92582874369.pdfIn PDF document text
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/2cuktmf1anar1f387ef0v92q3v/15557524039.pdfIn PDF document text
    • http://0965818789.com/CKEdit/upload/files/zipikak.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a9c67ea1a6a---95719936901.pdfIn PDF document text
    • https://fibaquitaine.fr/cebatrama/userfiles/files/lefelopisuvigojudinewu.pdfIn PDF document text
    • https://thaiwoodengames.com/files/upload/files/karusenaretovozido.pdfIn PDF document text
    • http://bualuang101.com/backoffice/upload/files/59283736935.pdfIn PDF document text
    • https://mpksieradz.pl/upload/file/37569024691.pdfIn PDF document text
    • http://taeguektour.com/FileData/ckfinder/files/20210620_0409FEB9D3E70162.pdfIn PDF document text
    • http://pelesiuvalymas.lt/i/File/sajexekozazonavipokomu.pdfIn PDF document text
    • http://hladonural.ru/upload_picture/zetasoronu.pdfIn PDF document text
    • http://hud101.vn/webroot/img/posts/files/waweroxasekamon.pdfIn PDF document text
    • http://hollandunitedreunion.com/clients/5/52/52f3fdf721cdccceb566e47094f1d9de/File/ninolenulijop.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/iuog7pq6nt9fnicvlnnl8pvbqg/18837389992.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_off0000d5aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5AA 18024 bytes
SHA-256: 5a6d73b4222b81ee2d23b38e40e7f0a4d61d6920f74e4e5154bf35cde3b8b942
font_01_sfnt_off00010502.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10502 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011d19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D19 11048 bytes
SHA-256: cdcace22d0e09c59fd429ab637c4c05d5aca63a813beadbd00816eaa934ffd8b