Malicious PDF — malware analysis report

Static analysis result for SHA-256 b56545a0fc57173b…

MALICIOUS

PDF

82.7 KB Created: 2021-10-06 16:44:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 772fb08eef10f9da74c593d46e2b3bd3 SHA-1: 29ec7b441a4d88c9c763a30fa2f9fa38cf032038 SHA-256: b56545a0fc57173be78e32b5bc381ac8fe15ef5bb978f5601a93421c96fadce9
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable domains and are structured as a link farm, a common technique for distributing phishing lures or malware. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://gulamanis.com/contents/files/40397277369.pdf In PDF document text
    • http://alompar.hu/uploads/content_files/files/mogobijutozugezet.pdfIn PDF document text
    • https://hunde-katzen.at/soubory/22626896443.pdfIn PDF document text
    • http://roomyab.ir/basefile/roomyabir/files/92796926351.pdfIn PDF document text
    • http://softtox.com/new/userfiles/file/41471604501.pdfIn PDF document text
    • https://osikovo.eu/webroot/img/content/files/61974293151.pdfIn PDF document text
    • http://www.bluefashion.cz/ckfinder/userfiles/files/bozuz.pdfIn PDF document text
    • http://edins.net/userData/ebizro_board/file/82345225673.pdfIn PDF document text
    • http://daiichihousing.net/uploads/news_file/80565516200.pdfIn PDF document text
    • http://manilag.com/FileData/ckfinder/files/20210927_67742028D9F284FF.pdfIn PDF document text
    • http://kenzoum.org/home/integrity/public_html/ckfinder/userfiles/files/49190275506.pdfIn PDF document text
    • http://louisamerino.com/userfiles/file/sorak.pdfIn PDF document text
    • http://tonioloclaudio.it/userfiles/files/32530989982.pdfIn PDF document text
    • http://tauroconsulting.pl/userfiles/file/45064105408.pdfIn PDF document text
    • https://dongciao.com/uploads/files/202109031646491194.pdfIn PDF document text
    • https://we-plus.tw/ckfinder/userfiles/files/xufikoropitupejidudo.pdfIn PDF document text
    • https://imagebuzz.net/ckfinder/userfiles/files/pakemefevilosijaf.pdfIn PDF document text
    • http://hamdannepal.com/userfiles/file/2904792862.pdfIn PDF document text
    • http://deltools.com/userfiles/file/25108926334.pdfIn PDF document text
    • http://pinzimoniofiumicino.eu/userfiles/files/20978705608.pdfIn PDF document text
    • https://indiantalentjunction.com/milan/media/gimolikozepadetevenebi.pdfIn PDF document text
    • https://living-stone.lu/userfiles/files/33979655284.pdfIn PDF document text
    • http://anitacalderon.com/ckfinder/userfiles/files/88925436231.pdfIn PDF document text
    • http://www.petercar0937494634.com/upload/img/files/83360775623.pdfIn PDF document text
    • https://dulsuc.cl/userfiles/file/90179367398.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=what+is+empirical+and+molecular+formulaPDF 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_off0000d950.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD950 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f162.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF162 19140 bytes
SHA-256: b7e516c9cea5b76718dd4aba73b60b943ad8b1bb2ef07a15a72c28e014e0c849
font_02_sfnt_off000123a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123A8 10976 bytes
SHA-256: 1e797191c1a641081b58dc34ac755cc279c541b79061b1fc5f4b40ffce7ce964