Malicious PDF — malware analysis report

Static analysis result for SHA-256 b291948c2f6d0dd5…

MALICIOUS

PDF

83.8 KB Created: 2021-09-19 04:27:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: f84e5aeb8bfdf7c3f90d41d8ee5c42d8 SHA-1: 129856ad5e8e5ca6db06a07b395afa8bca15e013 SHA-256: b291948c2f6d0dd5e919bc7cb972785a3e26227b98618ebbac5c8f6cdf2e8996
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains numerous embedded URLs, many of which are part of a link farm designed to obscure the ultimate destination, suggesting an attempt to trick users into downloading further content. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a pattern of using disposable hosting for multiple links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://nextgenship.net/upload/file/20210916163182787839.pdf In PDF document text
    • http://dongtienlamnghiep.com/upload/file/11625854169.pdfIn PDF document text
    • https://postelezmasivu-ostrava.cz/ckfinder/userfiles/files/45183201995.pdfIn PDF document text
    • https://www.colegiumaniucarei.ro/ckfinder/userfiles/files/37935413791.pdfIn PDF document text
    • http://yushendesign.com/images_fck/file/1630743911.pdfIn PDF document text
    • https://quangtriasianwindow.com/uploads/image/files/tidabidifudazaradodemoze.pdfIn PDF document text
    • http://fpempresa.cen.es/userfiles/files/fabotefejiloresawinovuse.pdfIn PDF document text
    • https://majorsagilekvaros.hu/uploads/file/71841200327.pdfIn PDF document text
    • http://chukgoobok.com/files/fckeditor/file/vitefonepumimoru.pdfIn PDF document text
    • http://ambvet-trefontane.eu/userfiles/files/zaxatutalijizoxep.pdfIn PDF document text
    • https://oxi-dental.ro/imagini_ws/37942059527.pdfIn PDF document text
    • https://pushtypathshala.com/demo/aims/files/images/files/82208823748.pdfIn PDF document text
    • http://papinchess.ru/userfiles/file/vedugenuwek.pdfIn PDF document text
    • http://deauville.ru/files/file/xojija.pdfIn PDF document text
    • http://electric-kernbichler.at/70630906274.pdfIn PDF document text
    • https://gulfsupremesa.com/ckfinder/userfiles/files/68935412171.pdfIn PDF document text
    • http://kaiyudachem.com/filespath/files/20210903181049.pdfIn PDF document text
    • https://tyko.pl/userfiles/file/famikizatimadubav.pdfIn PDF document text
    • http://mpu-beratung-brendle.de/userfiles/file/kaxawopiwujawo.pdfIn PDF document text
    • http://chinamakina.com/userfiles/file/32050315424.pdfIn PDF document text
    • https://korzayithalat.com/spot/admin/fckeditor/userfiles/file/momorotukobezamadezatad.pdfIn PDF document text
    • http://rqconsultores.com/userfiles/file/71679846574.pdfIn PDF document text
    • https://toptenstudy.com/upload/files/BodyFile__613BC9661D835.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139ea0defd86---96857307208.pdfIn PDF document text
    • http://noithatnhapkhaugiasi.com/luutru/files/jaxuxusimub.pdfIn PDF document text
    • http://artdealer.vn/upload/fckimagesfile/a5c94114b26b3babc582a88b2b182cef.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=crazy+chef+mod+apkPDF 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_off0000d5e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000edfb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDFB 10676 bytes
SHA-256: 3ea5f61e397e372b9349532365cae7ddd2a6c4e1e1c9fbb345f0994dccd4f259
font_02_sfnt_off00010685.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10685 22320 bytes
SHA-256: d1e477c657ea2eb8fb30303cba66afc8f0303f232499bc81ea0394b57223f46e