Malicious PDF — malware analysis report

Static analysis result for SHA-256 d6139f2dc50f7194…

MALICIOUS

PDF

82.9 KB Created: 2021-09-10 21:56:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 617ecd8f625933d4baafe1869a94b4f7 SHA-1: df5554fcd4b9d7c4f6797be74ed6e91f026066f4 SHA-256: d6139f2dc50f71946787010aee578a5f8a3959710f2f4847bb2b989973173495
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to compromised WordPress upload storage and disposable hosting sites. These links likely lead to phishing pages or further malware downloads.

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 https://chungcungoaigiao.vnpec.xyz/uploads/files/kelagumulel.pdf In PDF document text
    • https://ppkh.net/userfiles/file/69079812168.pdfIn PDF document text
    • http://www.sosonomo.com/ckfinder/userfiles/files/rirax.pdfIn PDF document text
    • http://bayernglobal.de/userVZ/file/tunanakominug.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613b3da8eddb8---53102856237.pdfIn PDF document text
    • http://the-bom.kr/upfile/files/rakesikibesigaranoxejuku.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fd053b7493---rajusetutivuvajukus.pdfIn PDF document text
    • http://aal.tw/uploads/htmlupload/files/29851755389.pdfIn PDF document text
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/ed555a45a65837ca1951f45046b4de13/bixusegexixo.pdfIn PDF document text
    • http://dotykbylinky.sk/_subory/subory/jevap.pdfIn PDF document text
    • https://kompaspt2.com/contents/files/98665081716.pdfIn PDF document text
    • http://knauto.com/upload/file///64845397158.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/gcurq9vrjfe3eiflbikhfnndf3/nupokodupebebuzamurigasa.pdfIn PDF document text
    • http://www.centralperdana.com/file/7435994690.pdfIn PDF document text
    • http://gibisch.org/files/files/40973132922.pdfIn PDF document text
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/17d613cdf84eab4a31e3651d4ded053c/jezirerepinikazokisuj.pdfIn PDF document text
    • http://www.fd.ntou.edu.tw/ckfinder/userfiles/files/togeritudadetitaze.pdfIn PDF document text
    • https://clic-essc.ch/ck/ckfinder/userfiles/files/ruxaloxesakewera.pdfIn PDF document text
    • https://permargi.com/files/galeria/files/junajef.pdfIn PDF document text
    • http://naturenhuman.com/app/webroot/userfiles/file/61909111353.pdfIn PDF document text
    • https://euronuts2009.ge/files/files/migemuwazaked.pdfIn PDF document text
    • http://geopraxis.it/userfiles/files/fosililatowuzalaxobofoka.pdfIn PDF document text
    • http://ttmplus.com/userfiles/files/lawafajog.pdfIn PDF document text
    • http://bitite.lv/media/txt/122/file/pefat.pdfIn PDF document text
    • http://zulassung4you.de/bilder/file/suxovuxafudo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=cast+screen+to+firestickPDF 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_off0000de83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE83 10408 bytes
SHA-256: 40e378aea097ee3fdd8ace7c312200e947877961c5e265188071a4c38508465a
font_01_sfnt_off0000f63e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF63E 18344 bytes
SHA-256: 9ba8c97d44d703506c46be8fa3b6a254f093f88c659008cb318caf527b6fc28e
font_02_sfnt_off000125e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1