Malicious PDF — malware analysis report

Static analysis result for SHA-256 73d546cbcc114f9b…

MALICIOUS

PDF

77.6 KB Created: 2021-10-06 12:07:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 4ff0df974bff5c82a9089639874a058d SHA-1: 77389ad21eff88493d187b21abe01256c902f661 SHA-256: 73d546cbcc114f9b091b8a6d3fc449af533fd9c9372163bd2c418dc160d84dfc
94 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV with a 'Pdf.Phishing.Trojan' signature. Static analysis revealed it functions as a link farm, containing 30 links across 24 distinct hosts, with a specific heuristic flagging it as a 'PDF_SEO_DISPOSABLE_LINK_FARM'. The embedded URLs and the PDF structure suggest an attempt to redirect users to potentially malicious or deceptive content.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.4212

Heuristics 4

  • 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
  • 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://dokturmice.com/ckfinder/userfiles/files/nukuzapewanokawavajo.pdf In PDF document text
    • http://muacuoi.vn/Pictures/files/17708562281.pdfIn PDF document text
    • http://bronnicy.inhome360.ru/admin/ckfinder/userfiles/files/remokumogopirudagage.pdfIn PDF document text
    • http://fgosvo.ru/files/files/9975107019.pdfIn PDF document text
    • https://telliogluhukuk.com/userfiles/file/28231254749.pdfIn PDF document text
    • http://woodlandhills.ilovepokebar.com/uploads/files/wawedugonovoxopukeko.pdfIn PDF document text
    • http://suurelepa.ee/data/file/65734356393.pdfIn PDF document text
    • https://ltes2.tw-goods.com/UserFiles/files/marosonadad.pdfIn PDF document text
    • https://vsetinrally.cz/userfiles/file/36140491444.pdfIn PDF document text
    • http://limobebe.com/userfiles/files/21834607568.pdfIn PDF document text
    • http://actlogistic.vn/upload/editor/files/86024326777.pdfIn PDF document text
    • https://opescom-store.com/uploads/FCK_files/file/rotevorawijasewefupudazu.pdfIn PDF document text
    • http://www.afurg.com.br/assets/ckfinder/userfiles/files/42665333061.pdfIn PDF document text
    • https://lodoshosting.com/calisma2/files/uploads/jabevipitifuvorosirixara.pdfIn PDF document text
    • https://myoffice.acqualive.com/uploads/files/9587948145.pdfIn PDF document text
    • http://vidol.eu/userfiles/file/56059036218.pdfIn PDF document text
    • http://mptech.vn/ckfinder/userfiles/files/rutavigonefev.pdfIn PDF document text
    • http://oshcongregation.com/userfiles/file/paragolepotewajowanutejut.pdfIn PDF document text
    • http://artc-polymers.com/upload/images/files/zidulosin.pdfIn PDF document text
    • https://ijtm.in/userfiles/file/xojipawu.pdfIn PDF document text
    • https://www.antoniopopolizio.it/ckfinder/userfiles/files/buwenepunerujusoti.pdfIn PDF document text
    • http://geostudio.eu/userfiles/files/1289685397.pdfIn PDF document text
    • http://healthywithhart.com/res/file/22087663235.pdfIn PDF document text
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/1615b443b3b0ad---85408767054.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=how+many+beats+does+a+quarter+note+receivePDF link annotation
    • 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_off0000db82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB82 11128 bytes
SHA-256: 1945c55e79eb1d02bd7e45b5a6ebc7e541a7ff5c5032bb5a3323c48d95549c1e
font_01_sfnt_off0000f554.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF554 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010d66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D66 17488 bytes
SHA-256: dac329038afef88fb52a0cb6106e7d49906646356f13cf77db1d6eee6cea4ace