Malicious PDF — malware analysis report

Static analysis result for SHA-256 d33f07a9f2bb06bb…

MALICIOUS

PDF

81.1 KB Created: 2021-09-22 18:59:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ad803218d85e307abc0d1da89e267306 SHA-1: 102a3bf8769a2715aacfcee706b3e390e599e7bc SHA-256: d33f07a9f2bb06bbf1e776cf851fb8c0a7008b87306607964a4791a8eba4cd96
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to lure users to potentially malicious content. The ClamAV detection and ML classifier strongly suggest a phishing or malware distribution intent. No scripts were extracted, but the heuristic firings and URL analysis are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://chcial.ru/uplcv?utm_term=virtual+machine+windows+10+android
    • http://solyaris.pro/admin/ckfinder/userfiles/files/jerajuz.pdf
    • http://nessium.fr/userfiles/file/6813998486.pdf
    • http://knowleangling.co.uk/ckfinder/userfiles/files/15414924273.pdf
    • https://flavio-tonon.it/public/file/volev.pdf
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a890f595dc---nasosoninomodup.pdf
    • http://speakingaboutnetworking.com/ckfinder/userfiles/files/gikapebizovaxa.pdf
    • https://chaletsuenodesol.de/files/fesozigefuparifosogev.pdf
    • http://xn--80aafbanafwvcftiqfecrg2a.xn--p1ai/pict/file/11643976170.pdf
    • http://pujcovnanaradi-tvarozna.cz/userfiles/files/20535122857.pdf
    • http://tropo-design.com/ckfinder/userfiles/files/10114752695.pdf
    • https://akilanews.com/ckfinder/userfiles/files/79870786942.pdf
    • https://llbyggodesign.se/UserFiles/files/1692386184.pdf
    • http://www.coverseg.com/uploads/ckfinder/files/baxobidijeku.pdf
    • http://househouse.it/userfiles/files/78874617798.pdf
    • https://hkbca.org/UploadFiles/file/20210920115302147.pdf
    • http://xy-interior.com/uploads/files/202109050507049911.pdf
    • http://hindustanadvancedsolution.com/t/tutorfirm/uploads/ck/files/71997560559.pdf
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/90d72d0e79a39839c4e322a963786874/25080004217.pdf
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/4be909f1fdf477df1c75cdbd048904b4/71141529710.pdf
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/f18badc5d0364096009ef047db8f6a9a/tadibakiwope.pdf
    • https://vnjhanoi.com/upload/files/32538824436.pdf
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/703923771811724d1adb86530bee7764/dabix.pdf
    • http://watdoenwevandaag.nl/upload/kogunefitegalibasexosuvab.pdf
    • https://a-metal.e-giant.net/archive/file/files/pujakanimavisud.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d8a8.bin
b6a4084bb840a12d4510b706b1046778978446bf085772722dd6341c5bf4649b
pdf-font-stream PDF embedded font (sfnt) at offset 0xD8A8 10964 bytes
font_01_sfnt_off0000f204.bin
8c01bdfe27a5be2ffc91cf5e346fad367e44f72949d584752660ae3a41c42005
pdf-font-stream PDF embedded font (sfnt) at offset 0xF204 17212 bytes
font_02_sfnt_off00011eb0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11EB0 16792 bytes