Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d371364b1e3e4b6…

MALICIOUS

PDF

94.5 KB Created: 2021-09-19 01:22:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 100acfd772a315ce0e99368b69b05e03 SHA-1: ebfe8bd45e92fd06f1cfe2f60a7acd11529f7190 SHA-256: 3d371364b1e3e4b67e47c547efcb1f01d644380732edacae9a9edd99ce6ed7c3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to host malicious content or redirect to phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

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://synerhu.ru/uplcv?utm_term=dark+heresy+second+edition+core+rulebook+pdf PDF link annotation
    • http://marcus-1.com/FileData/ckfinder/files/20210915_BD142EE84AB73CE8.pdfIn PDF document text
    • http://www.atsamuihaus.com/image/upload/File/92317168271.pdfIn PDF document text
    • https://www.cifphosteleriayturismo.es/ckfinder/userfiles/files/5829978179.pdfIn PDF document text
    • http://af.ssla.ru/images/fornews/files/mivilasomuroxuxanagilow.pdfIn PDF document text
    • http://castrolmintabolt.hu/images/upload/file/sipibuzixojorewukasuzozuw.pdfIn PDF document text
    • https://hotelgaric.com/upload/datoteke/42283562088.pdfIn PDF document text
    • http://rulada.by/upload/editor/files/54814818747.pdfIn PDF document text
    • https://giaphutelecom.com/tctt/sites/aaa/file/wirazamemajomejaserelujed.pdfIn PDF document text
    • http://konferencii.org/web/uploads/assets/file/53938294184.pdfIn PDF document text
    • http://kingbikeonline.com/images/upload/File/64515679675.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/16145c6cd1f566---jakarenokazujidapedowa.pdfIn PDF document text
    • https://alhurwallpaper.com/Files/files/tavosisat.pdfIn PDF document text
    • http://teraval.cz/res/file/62083610644.pdfIn PDF document text
    • https://thietkewebseo.com/webroot/img/files/xobepemojab.pdfIn PDF document text
    • http://www.ecrivains-consult.fr/easyonline/ckfinder/userfiles/files/7532324305.pdfIn PDF document text
    • http://tysons-cafe.com/uploads/files/30391155329.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145bbd5b99b6---mugoges.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/bgiib2o8on2tpvloe4adlsfhi9/52719709078.pdfIn PDF document text
    • http://byecook.com/ckupload/files/nitedezinudebedotareku.pdfIn PDF document text
    • https://deshpanday.com/ckfinder/userfiles/files/munuvirow.pdfIn PDF document text
    • http://yogaschoolofkerala.com/photos/editor/files/xakimizaxiso.pdfIn PDF document text
    • https://bhavanarayanaswamy.org/userfiles/file/36089311217.pdfIn PDF document text
    • https://mlspoland.co/files/file/8025290626.pdfIn PDF document text
    • http://morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613deb466a290---xutazomiza.pdfIn PDF document text
    • 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_off00010c99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C99 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000124b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124B0 11164 bytes
SHA-256: b51c3ad84788cc8e92e913995a87683def9c00895a84705e5af027e19b6fefbc
font_02_sfnt_off00013e8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E8A 17592 bytes
SHA-256: 5acc834b0fcd6e340595be15c435b6d3f60c07b7d6377e6827277f28ab21ff42