Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1bc3d878d52f6c6…

MALICIOUS

PDF

68.5 KB Created: 2021-09-29 00:11:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 08aac2c9d89c099678574a28ea91589e SHA-1: 89d04e66d3cffa5a1ad7707804909bdb0e49fbf6 SHA-256: b1bc3d878d52f6c655637ff55246b676fd9ce8537a6dea2e1f51e3d9b0d9053e
126 Risk Score

Malware Insights

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

The PDF was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. It contains numerous external URLs, with one specifically using a UTM term suggesting a lure for a hacked game version, pointing towards a phishing or malware distribution scheme. The presence of many links on disposable hosting further supports this. The document body is unreadable, but the overall structure and URL analysis strongly suggest a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://nomylo.ru/uplcv?utm_term=hack+version+of+shadow+fight+2+special+edition PDF link annotation
    • http://sayarbobinaj.com/file/44185214465.pdfIn PDF document text
    • http://barrybusiness-crm.com/ressource/devis-photo/files/49731008456.pdfIn PDF document text
    • http://domadoma.cz/userfiles/file/muxixunododaxujutofemow.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/ejegopolapobexuv.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/dubuvumugivivuzovutug.pdfIn PDF document text
    • https://newdesert.pl/userfiles/file/rajidetomutazerojekodotom.pdfIn PDF document text
    • http://hun777.hu/_user/file/nitagi.pdfIn PDF document text
    • https://jin-hung.com/userfiles/file/mozifofoxodotumoxixefom.pdfIn PDF document text
    • http://webinaris.training/ckfinder/userfiles/publics/files/88427290076.pdfIn PDF document text
    • http://nousgarage.com/userfiles/file/tubinenivik.pdfIn PDF document text
    • https://ego-sofa.tw/uploads/files/202109190756366918.pdfIn PDF document text
    • https://www.eecpowerindia.com/codelibrary/ckeditor/ckfinder/userfiles/files/wavenavopopetagutasotukur.pdfIn PDF document text
    • http://stlukesfp.org/ckfinder/userfiles/files/bupiwalubugiramimutulo.pdfIn PDF document text
    • http://www.juniorcollege.cl/ckfinder/userfiles/files/28872030880.pdfIn PDF document text
    • https://imihwa.com/uploads/image/20210914/files/20210914152934.pdfIn PDF document text
    • http://www.corazondelsol.es/ckfinder/userfiles/files/96906345751.pdfIn PDF document text
    • http://railwaysrailroads.com/upload_files/files/81481236955.pdfIn PDF document text
    • http://moriefrusca.com/userfiles/files/nuxibuwaje.pdfIn PDF document text
    • https://proxus.nl/file/21051155556.pdfIn PDF document text
    • https://ikorti-iao.com/userfiles/files/33446051940.pdfIn PDF document text
    • https://alternatifhirdavat.com/upload/ckfinder/files/jiguwomulujoburenenepasur.pdfIn PDF document text
    • http://aucoindeshalles.fr/menu/file/koniwezemirogelabufodi.pdfIn PDF document text
    • https://mobiligennari.com/userfiles/file/vonilegosulorosemepevitej.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_off0000ad62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD62 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c574.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC574 14708 bytes
SHA-256: 34f16efecfb5e58c225ebce7e9f49a74039c6f7626d605ae83a28d2ceab1d582
font_02_sfnt_off0000ea05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA05 11256 bytes
SHA-256: 3ba83c30bd277dc422b4726687db7cb403ebadc19a1d18403936a55f1b43b797