Malicious PDF — malware analysis report

Static analysis result for SHA-256 85e46eb6e540aea3…

MALICIOUS

PDF

69.3 KB Created: 2021-09-30 11:35:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 9e673c82775c41195f3afda936bdac5b SHA-1: 9b7137e9244cc8d72ac67d497cc3d117e8f07d83 SHA-256: 85e46eb6e540aea33ef345078c933d276aab0b31cc9274f19959d3af062b19b6
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains embedded JavaScript and a significant number of external URLs, many of which are hosted on compromised or disposable domains, suggesting a link farm designed to redirect users. The presence of embedded JavaScript points to its use in executing malicious actions within the PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://synerhu.ru/uplcv?utm_term=brutal+doom+para+android PDF link annotation
    • http://podhoru.cz/userfiles/file/67708507868.pdfIn PDF document text
    • http://djk-winkel.de/images/uploads/file/70270386445.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/161345c20b45e6---60076671472.pdfIn PDF document text
    • http://savvyais.com/userfiles/file/sigozikelobufefumikoku.pdfIn PDF document text
    • http://korsorlampang.net/user_img/files/wotopawopavuna.pdfIn PDF document text
    • https://cs168.tw/upfiles/editor/files/xoxonololi.pdfIn PDF document text
    • http://matchedtubes.de/userfiles/file/fomidiju.pdfIn PDF document text
    • http://ddaengshop.com/ckupload/files/1872811336.pdfIn PDF document text
    • http://xyr59.com/filespath/files/20210903203443.pdfIn PDF document text
    • http://levne-pohary.cz/UserFiles/File/wisugofasetuka.pdfIn PDF document text
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/9s9jg2bmhnqvcvtrfdor91h91j/50971481844.pdfIn PDF document text
    • http://napiarsaigh.com/images/761311575.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d88d1b8479---komuvolunonex.pdfIn PDF document text
    • http://musclecar-taps.com/js/upload/files/gijejogenumukifig.pdfIn PDF document text
    • http://racecross.com/upload/edito_fckeditor/file/jugofe.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bf5482cc4e---gamevujuwaluvubiw.pdfIn PDF document text
    • http://emirates-offshore.com/uploads/image/file/47228647934.pdfIn PDF document text
    • http://skrutit-probeg.ru/upload_picture/file/99229391781.pdfIn PDF document text
    • http://mtegl.wsystem.sk/userfiles/files/bogezorabarum.pdfIn PDF document text
    • https://datatalk.ilvzhou.com/upload/files/2021/09/202109111800517370.pdfIn PDF document text
    • http://www.companyforte.com/imagenes/editor/file/padenopifedapow.pdfIn PDF document text
    • http://wecans.net/_UploadFile/Images/file/bobet.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_off0000ae10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE10 10408 bytes
SHA-256: e8f37c78cbcd3bcc7cbca7a068cb6f48b8c946fcb590033ab690a96d5b24eb93
font_01_sfnt_off0000c589.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC589 16916 bytes
SHA-256: c5b8a721a890b92de6dc687512af5ec7cec949d9e373b0d4383fdbeaf1813fad
font_02_sfnt_off0000f019.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF019 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1