Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b726aee0fc002f7…

MALICIOUS

PDF

87.6 KB Created: 2021-07-12 23:10:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4058d8700d732fe5aca8be75a9dcee83 SHA-1: 13e7b8763d54b4aaad506f06f60900a86185eb1f SHA-256: 8b726aee0fc002f7b4bd2c97bd174f42b442377bce86a0965a515b4514ccbb98
156 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 functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and disposable domains, likely intended to lure users into downloading further malware or submitting sensitive information. The presence of multiple external URIs and link farm heuristics strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16094f067561fb---12957650011.pdf
    • http://doktor-okonski.pl/uploadimg/file/sevewixiw.pdf
    • https://luminex.pl/upload/file/zulolug.pdf
    • http://classicalgardenornaments.com/uplds/file/92160527759.pdf
    • http://khangvietdn.com/uploads/file/jitit.pdf
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/bc52c864c7b6b5b8e1f1337eb7c7d7c8/vonawirixej.pdf
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/khhtu7von6stbpqc8v1oek61q0/67592062957.pdf
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089a358372e3---gewebototurenokimijelilub.pdf
    • https://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/10f7cf87741b870899234d07b478793c/18420316384.pdf
    • http://lifecare4all.com/upload/files/zewowejijopikifurutozul.pdf
    • http://krzeptowski.pl/file/50492147562.pdf
    • https://lawpropertyconsultants.co.uk/wp-content/plugins/super-forms/uploads/php/files/ej2l7j96svopqe75g5qe8mq9ec/77318091027.pdf
    • http://bamt.be/wp-content/plugins/formcraft/file-upload/server/content/files/1607a3fde7c576---97025992040.pdf
    • http://gagutp.com/sa_upload/userfiles/file/20210521220427.pdf
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/cci415pgffvdv2dl38u165pp71/5197780101.pdf
    • http://iseveranscopy.com/upload/editor/file/29014833381.pdf
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/86c14c0ea73d75aed8d0c4645fc6af20/93377958484.pdf
    • https://leo-translate.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1608998bda0e3d---60345398893.pdf
    • http://hifitness.hu/userfiles/file/losefalibazijegivagapeta.pdf
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160889c305c1c4---mironinomakun.pdf
    • http://planbmedia.hu/files/16118079974.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=berne+and+levy+physiology+latest+edition+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f16f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF16F 16792 bytes
font_01_sfnt_off00010986.bin
d50112d7d1ae911cbe7295ef8e571e628d939057b6d76884f556a480c85e63e8
pdf-font-stream PDF embedded font (sfnt) at offset 0x10986 11008 bytes
font_02_sfnt_off000122d8.bin
214e234dbd4ef4b0cf402b7f3ce89251caf78b21a3e1a7852e5cf23580c9d674
pdf-font-stream PDF embedded font (sfnt) at offset 0x122D8 17668 bytes