Malicious PDF — malware analysis report

Static analysis result for SHA-256 87eef91ff1ae5f14…

MALICIOUS

PDF

81.3 KB Created: 2021-09-11 20:58:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e0e4e510dc07097b1eae0d2dcc53e84a SHA-1: 9ec3eaf7b74dbce2328bdce45b4e9695121b5f09 SHA-256: 87eef91ff1ae5f1463db2c6654eaebb4c39089a3cfff79cacfd1da8cfa988a21
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users to potentially malicious sites. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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=how+to+force+install+apps+on+android PDF link annotation
    • http://hoanggiaphatland.com/uploads/image/files/piduritodu.pdfIn PDF document text
    • http://studiotecnicoligioni.com/userfiles/files/13978899912.pdfIn PDF document text
    • https://noventa.cz/media/files/file/porufosud.pdfIn PDF document text
    • http://rivucota.com/upload/files/16888698179.pdfIn PDF document text
    • http://ramenzoni.eu/userfiles/files/wixupewazon.pdfIn PDF document text
    • https://khambenhxahoi115.com/images/files/tirutogubewidune.pdfIn PDF document text
    • https://bikeid.net/ckfinder/userfiles/files/753118534.pdfIn PDF document text
    • http://hemeringen.de/ckeditor_ablage/userfiles/files/3448384229.pdfIn PDF document text
    • http://fantalife.nl/userfiles/file/kinuposiwijeg.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/16135d022ce5a7---20286850108.pdfIn PDF document text
    • http://hengtaixin.com/HangShun/ckfinder/userfiles/files/kukizekebaterasirekux.pdfIn PDF document text
    • https://cobrawire.com/userfiles/files/reruxekijabadovur.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161314ce82248e---zuwosiw.pdfIn PDF document text
    • http://techscreening.com/userfiles/files/6899742893.pdfIn PDF document text
    • https://www.funes.gob.ar/ckfinder/userfiles/files/lugosupuzanogokixawotin.pdfIn PDF document text
    • http://svatba-emi.com/uploads/pages/files/50897662543.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/r0qnu1b022j38k59940s223erl/zasagakiv.pdfIn PDF document text
    • http://worldplastsolution.com/ckfinder/userfiles/files/nedifetepixedevagovusidim.pdfIn PDF document text
    • http://dailyliving.nl/ckfinder/userfiles/files/fuwobokawisunadumuwaz.pdfIn PDF document text
    • https://5udua.com/contents/files/38405661466.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/161384a5b91fdd---bifebekijejelunusu.pdfIn PDF document text
    • https://pmfegypt.com/userfiles/files/38050417799.pdfIn PDF document text
    • http://italianopizzeria-pg.com/uploads/files/zabugebex.pdfIn PDF document text
    • http://solyaris.pro/admin/ckfinder/userfiles/files/56784770809.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_off0000da1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA1D 17116 bytes
SHA-256: bc0baacf6aa06f4e9e162e9fe7d3518a19636568016dc52798c5fd54ec2e3d98
font_01_sfnt_off0001065f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1065F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011e76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E76 10688 bytes
SHA-256: e0df71a197e494aeb1613d85a0b668377b746973bfd39d31d128775dceaeafc4