Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4eb3b1e2c92605f…

MALICIOUS

PDF

112.4 KB Created: 2021-09-05 01:09:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: f3e900f16a504ce95690fc964f35d448 SHA-1: 7dc35b9c1309468f79070833298e4a399f606651 SHA-256: f4eb3b1e2c92605f0e3dbc0573bdbef9258b9a8b889d094cd888607192d71865
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to lead users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://goldnumber.info/userfiles/file/jopokit.pdf In PDF document text
    • https://leciv.fr/uploads/FCK_files/file/5860345360.pdfIn PDF document text
    • http://sieuthivatlieuhoanthien.com/upload/files/42155749656.pdfIn PDF document text
    • https://newoptic.mn/uploads/files/79014635372.pdfIn PDF document text
    • http://fluitec.fr/ressource/site-image/files/97698230949.pdfIn PDF document text
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/ra2067lrbskl95sctmni32bcmm/zalotidazoliwevu.pdfIn PDF document text
    • http://bisenzia.it/userfiles/files/94209180543.pdfIn PDF document text
    • http://fabrikando.com/cmsimple/images/file/jagov.pdfIn PDF document text
    • http://alompar.hu/uploads/content_files/files/17275063775.pdfIn PDF document text
    • https://dannysacademy.com/ckfinder/userfiles/files/pefipevowubezuwewidaw.pdfIn PDF document text
    • http://kapli74.ru/upload_picture/23750386568.pdfIn PDF document text
    • http://ruihuitax.com/files/file/difisewis.pdfIn PDF document text
    • http://copy2d.com/ftp/image/file/72141788997.pdfIn PDF document text
    • http://dishandspoonproductions.com/ckfinder/userfiles/files/44943414529.pdfIn PDF document text
    • http://bjsixiang.com/jingkelun/userfiles/files/20210723043127.pdfIn PDF document text
    • http://uelzecht.lu/userfiles/files/beren.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f4463ac88af---nosubup.pdfIn PDF document text
    • http://maivietnamesecotati.com/uploads/files/zobamafopomidanowixizatog.pdfIn PDF document text
    • https://giasidaily.com/uploads/userfiles/file/53646780118.pdfIn PDF document text
    • https://kvizek.hu/ckfinder/userfiles/files/vubebimofilupom.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160729b855e7a2---26414625133.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1609b288ea6615---zifojo.pdfIn PDF document text
    • https://alutat.com/data/file/vivajatokupegi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=britannia+deck+plan+pdfPDF 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_off000157f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x157F8 16736 bytes
SHA-256: 1fd37312ad574eb5b4e80eb433cd13bb3d917bc6cc7c11e3d3689fbc332557a3
font_01_sfnt_off0001839b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1839B 10468 bytes
SHA-256: 76d127957b0f3468997d4f82eadd1c43eee38f493ede68b307eb5e993d4ba2c7
font_02_sfnt_off00019b78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19B78 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1