Malicious PDF — malware analysis report

Static analysis result for SHA-256 af3c033fd16ddfbc…

MALICIOUS

PDF

74.3 KB Created: 2021-09-26 01:56:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 81743d9a32e2c811369eff7a301974a1 SHA-1: e904c4a8b7fa2ae6d71d8065074711f2dc1d0764 SHA-256: af3c033fd16ddfbc4ac3ee1d6c7cdc2cf9089486d1d82ef5b0b36e3dbd78d310
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous embedded URLs, suggesting it functions as a link farm or phishing lure. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using disposable hosting for a large number of links, a common tactic for distributing malicious content or conducting phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://tenfci.org/userfiles/file/49742768576.pdf In PDF document text
    • http://rsti.biz/files/fck/file/vurukapo.pdfIn PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/9vs8vpdkprjnvlka76cpl4hc29/nofugulefalegavomanoj.pdfIn PDF document text
    • http://signfabapp.com/ckfinder/userfiles/files/zojojele.pdfIn PDF document text
    • https://isleo.com/i_photos/file/57352866388.pdfIn PDF document text
    • http://snailgame.ru/upload/files/20210919092159.pdfIn PDF document text
    • https://jyapa.com/jhuoyue/uploadfiles/bafujatumekolorufef.pdfIn PDF document text
    • http://aroma-es.red/yamituki-n/uploads/files/xovifusuzedafivorom.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f36b1bd5ed---12190298196.pdfIn PDF document text
    • http://lechioutdoor.com/userfiles/file/viruzuletavukadeg.pdfIn PDF document text
    • https://citytrafik.nu/images/file/jejiwavufelavejixeji.pdfIn PDF document text
    • http://diamantina-joaillerie.com/ckfinder/userfiles/files/93166064495.pdfIn PDF document text
    • http://plkorea77.com/ckupload/files/34368994110.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/gegonedisav.pdfIn PDF document text
    • http://hyswimpool.com/userfiles/pikoxilitamufemu.pdfIn PDF document text
    • http://nuovojob.com/userfiles/files/redadugorusesig.pdfIn PDF document text
    • http://www.lbtfilm.com/uploads/files/nivanufiju.pdfIn PDF document text
    • http://nationshield.ae/userfiles/files/xijedib.pdfIn PDF document text
    • https://doanandieuduong295doson.vn/namthuan/images/news/files/jiwamixejuvijegabowo.pdfIn PDF document text
    • https://sitpchemcieszyn.pl/_sitpchem/file/83805452034.pdfIn PDF document text
    • http://ornito-silesia.eu/userfiles/file/xiwapofot.pdfIn PDF document text
    • http://firegallery.ru/img/upload/90875757384.pdfIn PDF document text
    • https://hfbee.tw/upload/ckfinder_temp/files/20210912043639.pdfIn PDF document text
    • https://mamadona.ru/ckfinder/userfiles/files/bukozevekopepixivevigapiv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=vampire+academy+shadow+kiss+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_off0000bb12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB12 10900 bytes
SHA-256: 57886f52a058f7c9292f7a889340340bb68e36676f8b8a691f7509a4997eb575
font_01_sfnt_off0000d45e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD45E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ec70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC70 18364 bytes
SHA-256: 5c5ce84287f6cfcf3247053d992fcb03d555576ff4f48cfca07d2a99217f1469