Malicious PDF — malware analysis report

Static analysis result for SHA-256 8031804ad4dde454…

MALICIOUS

PDF

83.4 KB Created: 2021-09-17 16:00:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: e701ea841ecad6483e78614f835e72f2 SHA-1: 7d422079df8d6c5f4d497675421f623578b9c736 SHA-256: 8031804ad4dde4540125701be474951e106571cce31ebdac3fca37c6e86c354f
134 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains embedded JavaScript and numerous external URIs, flagged by heuristics as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to redirect users to these external sites, which are then used to host further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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
  • 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 http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1613875a53ae31---59052856067.pdf In PDF document text
    • http://techbico.vn/uploads/image/files/59989379760.pdfIn PDF document text
    • https://certifiedcollisionrepair.com/home/cert/public_html/ckfinder/userfiles/files/23805556312.pdfIn PDF document text
    • https://agroadvanced.com/app/webroot/newsletters/editor/files/nitepimusetegopefikowumaj.pdfIn PDF document text
    • https://xn--bankkrtya-41a.hu/js/ckfinder/userfiles/files/17019915412.pdfIn PDF document text
    • https://claudiodituri.it/uploads/82634165947.pdfIn PDF document text
    • http://www.parkwaytransplant.com/media_upload/upload/files/vixob.pdfIn PDF document text
    • https://jensbrode.de/files/file/15779102704.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/16143b6342a34d---lakejitadagibesetaz.pdfIn PDF document text
    • http://xn--80aiddhbkcq5bcaz.xn--p1ai/upload/files/bebajaxam.pdfIn PDF document text
    • http://tomekorea.com/userData/board/file/79296269871.pdfIn PDF document text
    • http://gyogytornasz.hu/editor_up/33245014820.pdfIn PDF document text
    • http://mega.kz/media/upload/files/91304896897.pdfIn PDF document text
    • https://unitjaya.com/contents/files/nuvinunuxumewelop.pdfIn PDF document text
    • http://ituor.ir/basefile/chartermeinfo/files/37812665120.pdfIn PDF document text
    • http://utpcomp.ru/uploads/files/fukizop.pdfIn PDF document text
    • http://nickelsgrafikdesign.de/ckfinder/userfiles/files/jewejasokejadevowejijavi.pdfIn PDF document text
    • https://sofanet.ro/ckfinder/userfiles/files/sifovajisibujiwik.pdfIn PDF document text
    • http://safarang.com/basefile/files/11157614312.pdfIn PDF document text
    • https://minhkygroup.com/luutru/files/bofekumokofabuwuwiditejir.pdfIn PDF document text
    • https://sharmtocairo.com/userfiles/files/borigo.pdfIn PDF document text
    • http://rexant.by/upload/editor/files/nufufoxovabulowovo.pdfIn PDF document text
    • http://baovephuongtroi.com/vietkiendo/upload/file/tibifaxepolaxizuf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=how+to+make+my+phone+securePDF 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_off0000e14f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE14F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f961.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF961 17720 bytes
SHA-256: 382f873a04b4eade080a7cc91de148947428007705d66abdd5b87d439da39a6b
font_02_sfnt_off00012793.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12793 10884 bytes
SHA-256: e0910c85eeb45d88aba8f157e9f3560c4125a85fe633fb92764c979e859a9a64