Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb8e9777c4e5c7bf…

MALICIOUS

PDF

81.9 KB Created: 2021-09-24 01:18:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 7e7024b32a55baa9e1507035ddcad911 SHA-1: 94ab6824b151e78c3d6b9c24cf864276e7392177 SHA-256: fb8e9777c4e5c7bfedd52b56d383302cb137bd11d652f62319530119208627bd
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to PDF files hosted on various domains, suggesting a link farm or distribution network. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a pattern of using disposable hosting for link aggregation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://gs-metals.com/filespath/files/20210912164836.pdf In PDF document text
    • https://mimpisiluman.com/contents/files/lekakupenanises.pdfIn PDF document text
    • http://prestopc.it/upload/file/fenizife.pdfIn PDF document text
    • https://elitstroycraft.ru/source/file/maxodelixu.pdfIn PDF document text
    • http://creativetechno.in/userfiles/file/47193532425.pdfIn PDF document text
    • http://spbi.cz/res/file/55557023950.pdfIn PDF document text
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/618738d37b8cb1e85194d9d2fef07369/wiwawujodataw.pdfIn PDF document text
    • http://104450wp19.agentcentrum.com/userfiles/files/lixivokenufexusirapadexa.pdfIn PDF document text
    • https://cplastik.eu/data/cms/file/30452976996.pdfIn PDF document text
    • http://kfgame.snailgame.ru/upload/files/20210920040819.pdfIn PDF document text
    • http://xn--h1acbpobggs.xn--p1ai/data/files/89554666517.pdfIn PDF document text
    • http://vivo-mebel.ru/upload/file/63557696129.pdfIn PDF document text
    • http://nemdanangpho.com/uploads/2021-09-02/images/files/8515946695.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613251ab13d59---tafobonega.pdfIn PDF document text
    • http://khaskhaan.mn/uploads/userfiles/files/gutevipuwanuselagetojenu.pdfIn PDF document text
    • http://www.tahi.hu/ckfinder/userfiles/files/49664120981.pdfIn PDF document text
    • http://sushikyototogo.com/uploads/files/87039376868.pdfIn PDF document text
    • http://daimarconstrucciones.com/images/admin/file/nalozexobabokulabukizokat.pdfIn PDF document text
    • https://hizlipin.com/calisma2/files/uploads/90420066604.pdfIn PDF document text
    • http://pizzeria-millemiglia.de/app/webroot/img/editor/file/livomunirexesabenijuwiso.pdfIn PDF document text
    • http://begemot-rus.com/uploadfiles/file/2021091414072273499.pdfIn PDF document text
    • https://blueparadise.pl/userfiles/file/67577309190.pdfIn PDF document text
    • http://levne-pohary.cz/UserFiles/File/bafela.pdfIn PDF document text
    • https://itscebu.com/upload/file/20210913094824.pdfIn PDF document text
    • https://emenu.hu/editor_up/73892319084.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=national+geographic+magazine+for+androidPDF 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_off0000d894.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD894 18556 bytes
SHA-256: 62a940a5adf638f2047e451efeead042656dd77bcb73986f31b0711635587880
font_01_sfnt_off000108dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000120f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120F4 10936 bytes
SHA-256: a4d756d516dec43168ef02bf2c95a663698721a9cfc99c23789902289556312e