Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d4cb411d1e1e8a4…

MALICIOUS

PDF

84.4 KB Created: 2021-09-17 07:18:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 28fc01ed7ffdcf146f35197dc938a7cf SHA-1: e362f3cebc923cb94d1a4552b5cc64fcc57a9d6f SHA-256: 8d4cb411d1e1e8a479eabcb513d4855d78c94639ea9457676067d7bd442669aa
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm or phishing lure. The document body is heavily obfuscated, preventing a clear understanding of its specific content, but the overall structure and URL analysis indicate a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613b255b06497---nawiwipuxulapewati.pdf In PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16131af97dde70---zafekirapune.pdfIn PDF document text
    • http://tostonet.cl/ckfinder/userfiles/files/badelunisaki.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161330ed0020ba---92308169796.pdfIn PDF document text
    • https://www.cifphosteleriayturismo.es/ckfinder/userfiles/files/5829978179.pdfIn PDF document text
    • http://www.me.ntou.edu.tw/ckfinder/userfiles/files/20210904_075027.pdfIn PDF document text
    • http://cokhilegia.com/upload/files/rutepulamirokajugobejir.pdfIn PDF document text
    • https://alcc.c-zentrix.com/ALCC/mail_attachments/multitenant-ws-01/1/1630830414.pdfIn PDF document text
    • http://www.rajpuc.pl/pics/file/rupewokonipebavumosegole.pdfIn PDF document text
    • https://mma-montessori.com/admin/ckfinder/userfiles/files/dubojaxiboxa.pdfIn PDF document text
    • http://xn----7sbicwad4afgcgd5aph7d5e.xn--p1ai/ckfinder/userfiles/files/77317171051.pdfIn PDF document text
    • http://investin-khj.ir/ckfinder/userfiles/files/48885200332.pdfIn PDF document text
    • https://www.sophrologue-nimes.fr/upload/news/files/97870733885.pdfIn PDF document text
    • http://bsinteriordesigner.com/userfiles/files/62235063609.pdfIn PDF document text
    • http://stavclearing.ru/upload/files/10542832749.pdfIn PDF document text
    • http://thomasgearon.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/durebigovazisafowejojog.pdfIn PDF document text
    • http://hsi-international.com/ckfinder/userfiles/files/62702027280.pdfIn PDF document text
    • http://chizclean.ru/files/fck/file/zegivinufuxila.pdfIn PDF document text
    • https://serka.com/serka/upload/files/bumin.pdfIn PDF document text
    • http://cuacuonnhaxuongbinhduong.com/upload/files/resokuxozekozifevufap.pdfIn PDF document text
    • http://thewhitmerlawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/padoxebezetad.pdfIn PDF document text
    • http://szyqjsj.com/UploadFile/file/20210917085744160.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/161422e1451500---kawim.pdfIn PDF document text
    • http://stagegator.scorchmark.com/stagegator/ckfinder/userfiles/files/gowokikebururipibuno.pdfIn PDF document text
    • https://inprovitargentina.com/ckfinder/userfiles/files/28494748262.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=samsung+galaxy+a3+sms+ton+%C3%A4ndernPDF 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_off0000dd2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD2C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f543.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF543 11316 bytes
SHA-256: 0985323bac8b62e2035e9e59cd6418bc9f6ee75f6b4c616b661a8025bf6f370d
font_02_sfnt_off00010f41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F41 19216 bytes
SHA-256: 9fd38af7e5d79264898debb261f5c0c23af88b97c69b04d8bb914c92e3a5ea40