Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d41eb635f51b472…

MALICIOUS

PDF

79.5 KB Created: 2021-09-08 13:16:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 7f149814d19f83fd66a1e4340cd54603 SHA-1: daecbfd31ecc4e3c024461f689ecb3dee9439110 SHA-256: 5d41eb635f51b472d876ed1ce13b62e10bf564233722f9f48b5451b199cc2773
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised upload storage or disposable hosting, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or SEO manipulation. The embedded JavaScript is likely used to facilitate redirection or further malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://bestcoloringpages.com/userfiles/file/kuvunoxegilobuzarowusip.pdf In PDF document text
    • http://scandinavia-ex.com/images/blog/file/lakive.pdfIn PDF document text
    • http://radio-salsa.fr/php/rs/filesupload/file/rudijejejunasenuzezojifeb.pdfIn PDF document text
    • https://landatur.com/files/galeria/files/rufelodegimu.pdfIn PDF document text
    • http://daiichibus.vn/uploads/news_file/zevufupe.pdfIn PDF document text
    • https://www.adom.biz.pl/ckfinder/userfiles/files/36816940492.pdfIn PDF document text
    • http://pekbdt.com/filespath/files/20210903033008.pdfIn PDF document text
    • http://banerjeetourspecial.in/ckfinder/userfiles/files/xibexo.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/161336bca3046b---rutozejedixajuj.pdfIn PDF document text
    • http://nhuaduongnhapkhauaz.org/upload/files/lipiruwurusosovinufipisuz.pdfIn PDF document text
    • http://teusz.pl/UserFiles/file/68797012937.pdfIn PDF document text
    • http://ciskmv.com/css/file/lemetepovove.pdfIn PDF document text
    • http://tk-weld.com/images/library/File/rekovinokafeba.pdfIn PDF document text
    • http://addisonplaza.abwingsmd.com/uploads/files/21771269392.pdfIn PDF document text
    • http://sabaispa.net/userfiles/file/7162510513.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16138316dbc7dc---85667681650.pdfIn PDF document text
    • http://bukharaalpharetta.com/sites/default/files/file/junovusakumas.pdfIn PDF document text
    • http://hzbmsj.net/images/upload/File/vafuxurubemufakiwolad.pdfIn PDF document text
    • https://interativacorretora.com/fotosempresa/files/tedodid.pdfIn PDF document text
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/03ed098d2e3187a87824dea99a7a5fbd/mimivikuroradatedos.pdfIn PDF document text
    • http://www.jacenter.org/js/ckfinder/userfiles/files/90677714395.pdfIn PDF document text
    • http://tuderprogettazione.it/userfiles/files/duzunomofu.pdfIn PDF document text
    • http://ambvet-trefontane.eu/userfiles/files/jiwewixubuno.pdfIn PDF document text
    • https://infotechloyalty.com/bot/ckfinder/uf/files/doxozasutatolifafopo.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135ef99eb6ac---bimunajumulononunuvir.pdfIn PDF document text
    • https://heks-tech.com/app/webroot/userfiles/files/95860168300.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=history+of+english+literature+pdf+william+j+longPDF 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_off0000d108.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD108 11368 bytes
SHA-256: de3ca110ad8105a40108c5a9d7055d4d552adf45314df1a5f4b81f38f9e15506
font_01_sfnt_off0000eb6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB6E 16908 bytes
SHA-256: bb3fb3ceceef0293621c3b2d2f7c3cd40ebf3a44cb5f1f7dfa2514ea0d722946
font_02_sfnt_off0001179a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1179A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1