Malicious PDF — malware analysis report

Static analysis result for SHA-256 59e555c6d811fce4…

MALICIOUS

PDF

86.4 KB Created: 2021-09-18 12:24:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: b6bef5c21b418e72ae42c0828dcb4359 SHA-1: 680d9d5ff83d938ec66a2e0fca1205199a02862b SHA-256: 59e555c6d811fce48c559af6d330ed780dc1fd661c9eb016d60d46cefe6e24f4
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to domains associated with compromised CMS uploads or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. The file's structure and link distribution pattern suggest it's intended as a lure, likely for spearphishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://vatlieutaphu.com/upload/files/kuzuw.pdf In PDF document text
    • http://mdtrend.hu/files/file/83878717278.pdfIn PDF document text
    • http://cuadepthanglong.com/images/ckeditor/files/gikupan.pdfIn PDF document text
    • http://jfe.hk/userfiles/92713513739.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/161407e2e81331---juzevabebavobelo.pdfIn PDF document text
    • http://kimsanghun.com/upload/userfiles/file/2021951445433558.pdfIn PDF document text
    • http://parquet-cortes.fr/data/Files/wakepetofegavedu.pdfIn PDF document text
    • http://npas.ru/pic/file/7507279806.pdfIn PDF document text
    • https://ski-valloire.com/ckfinder/userfiles/files/94656972530.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/161379da657c63---39497272988.pdfIn PDF document text
    • http://ranfeng.com/userfiles/file/2021-9///20219132137184266.pdfIn PDF document text
    • https://rezilta.com/psum/admin/userfiles/file/55089369449.pdfIn PDF document text
    • https://ckeditor.pamlskovnik.cz/ckfinder/userfiles/files/45665701184.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613a1705173d9---93519513475.pdfIn PDF document text
    • http://dija.lv/public/userfiles/file/23274728920.pdfIn PDF document text
    • http://sabaispa.net/userfiles/file/xuzovurateko.pdfIn PDF document text
    • http://motolargo.pl/userfiles/file/15220894328.pdfIn PDF document text
    • http://tc-antey.ru/uploads/files/21914597694.pdfIn PDF document text
    • https://robindayne.com/ckfinder/userfiles/files/kozerilorotal.pdfIn PDF document text
    • http://youngthisyear.com/ckfinder/userfiles/files/99038782842.pdfIn PDF document text
    • https://amrapalispot.com/userfiles/file/mejezafisuzow.pdfIn PDF document text
    • https://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/ff6857a756339782663cbf0ab9e23df4/82155103802.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1613a867712c1d---giwup.pdfIn PDF document text
    • http://begemot-rus.com/uploadfiles/file/2021091813081873499.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=40+60+house+plan+east+facing+3dPDF 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_off0000eb5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB5F 11340 bytes
SHA-256: 7edd6eeb2dee2f19993fe80a289e6ca4f21b1024897a4c5a2c85c4f6a832149d
font_01_sfnt_off000105da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105DA 17828 bytes
SHA-256: abb76e485da62998b5c629fb4f07de0137142bcd52e8a2b5b6b80faee11e2786
font_02_sfnt_off00013427.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13427 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1