Malicious PDF — malware analysis report

Static analysis result for SHA-256 2cf77f3289e73010…

MALICIOUS

PDF

76.8 KB Created: 2021-09-18 18:01:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: df16a4e363c9f6bf263c9584fa0088d2 SHA-1: 849c5a6c70d155655f6613461d48e8daaa58c820 SHA-256: 2cf77f3289e7301097eb534bc4d0f84fd091febc0d48a0948ad764388764399d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file is a PDF containing numerous links to other PDF files, many hosted on compromised or disposable domains, indicating a link farm designed to obscure malicious intent. The ML classifier and ClamAV detection strongly suggest malicious content, likely phishing or malware distribution. Although no scripts were explicitly extracted, the nature of the link farm and the PDF format suggest potential for embedded malicious JavaScript or exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.ondebiz.com/userfiles/file/xumatod.pdf In PDF document text
    • http://hk888.edo2008.com/com/comimg/file/20210909_015132_191.pdfIn PDF document text
    • https://istanajp.net/contents/files/82297318143.pdfIn PDF document text
    • http://parilka.by/var/upload/file/fominupasajojinabidugu.pdfIn PDF document text
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/5g3l7dibgudn2avoebfm0uf82q/pizejuro.pdfIn PDF document text
    • http://www.instalacionescueto.com/nueva/ckfinder/userfiles/files/29225600046.pdfIn PDF document text
    • http://stroykap.com/application/views/stroykap/userfiles/file/47959040093.pdfIn PDF document text
    • https://cowichanseniors.ca/userfiles/file/pakesukota.pdfIn PDF document text
    • http://taiwanquinoafamily.com/shopadmin/upload/files/rozojod.pdfIn PDF document text
    • http://pm-property.pl/userfiles/file/97815228446.pdfIn PDF document text
    • http://mkpstroitel.ru/upload/files/mupul.pdfIn PDF document text
    • http://cappellastudio.it/userfiles/files/zujimi.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/le8649f5ifqc3pu60n08vkl6t4/gagaxifodisonafo.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/16141235880085---67310445561.pdfIn PDF document text
    • http://chemonova.com/FCKeditor/file/80736620225.pdfIn PDF document text
    • http://nobody-films.com/bpms/includes/fckeditor_uploads/userfiles/file/26497716663.pdfIn PDF document text
    • http://xn--989ap7r0xbd5x.com/upload/fckeditor/file/zekixudefafusulurejaj.pdfIn PDF document text
    • https://godparents4tz.org/home/god/public_html/ckfinder/userfiles/files/76146718887.pdfIn PDF document text
    • http://ksklinika.ru/ckfinder/userfiles/files/7533334381.pdfIn PDF document text
    • http://hyunshin.net/userfiles/file/sugaruzewe.pdfIn PDF document text
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/8948aa53eb04817d87746ebfbab9d95e/xibeletawerexisiragibok.pdfIn PDF document text
    • https://rwd.webseo.tw/upload/files/finegojutuxezidaxafekivo.pdfIn PDF document text
    • http://nemeckystrakac.sk/editor_uploads/files/35238930908.pdfIn PDF document text
    • http://danies.ru/ckfinder/userfiles/files/7662010024.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=work+profile+app+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_off0000c8af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8AF 17548 bytes
SHA-256: efa24ae8e53e1418e9e66053564489a585b7cdc31bd6745d9bbda3275bce6784
font_01_sfnt_off0000f6a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6A2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010eb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EB9 10312 bytes
SHA-256: d0c88ed1af3db8a3e9b747618a37accfea8af7bfb85a32006df3a95ca3116068