Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf832b90386f5ce0…

MALICIOUS

PDF

83.3 KB Created: 2021-09-12 10:04:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: af597712a21cdf7fbed29c87943a7072 SHA-1: 081ba04cfed1fb6f3d45e9244457a69e0ec7f427 SHA-256: cf832b90386f5ce099d545ff2ae593550522046aed7c680acef10fcdf31f3b75
146 Risk Score

Malware Insights

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

The file is a PDF identified as malicious by ClamAV and an ML classifier. Heuristics indicate it functions as a link farm, directing users to numerous disposable PDF hosting sites, consistent with phishing or scam lures. The 'SE_CALLBACK_LURE' heuristic further suggests a potential callback phishing or tech-support scam pattern, although no specific callback number was extracted.

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
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://disonde.com/filespath/files/20210906044938.pdf In PDF document text
    • http://regmac.net/userfiles/files/23097643987.pdfIn PDF document text
    • https://aarushimukhwas.idealviews.com/userfiles/files/nadira.pdfIn PDF document text
    • https://lrdreamteam.com/files/files/file/InfoProduct/file/safekogepujofitamis.pdfIn PDF document text
    • http://oreade-breche.fr/userfiles/file/1855401320.pdfIn PDF document text
    • https://swalaya.in/userfiles/file/nevojasowixuzudenor.pdfIn PDF document text
    • http://tiszaladany.hu/upload/file/tujuvaxofagukiwavefudi.pdfIn PDF document text
    • http://inbeeldt.nl/userfiles/file/48347598192.pdfIn PDF document text
    • http://op-gold.com/ck_image/files/84799794281.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f1d6d627b8---5383995754.pdfIn PDF document text
    • http://rlponder.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/mapifomokobaxe.pdfIn PDF document text
    • https://247christianity.org/fckeditor/userfiles/file/419231602511630711761.pdfIn PDF document text
    • https://bilalyapidekorasyon.com/userfiles/file/46665244283.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/6dfe255e2b88550772558330e72cbf22/7341060614.pdfIn PDF document text
    • http://gpe-el.pro/ckfinder/userfiles/files/xanemizuzoxapurukolejigus.pdfIn PDF document text
    • https://gs-hemeringen.de/ablage/userfiles/files/nuzaxovub.pdfIn PDF document text
    • http://www.supair-lux.hu/ckfinder/userfiles/files/forarivepunawakor.pdfIn PDF document text
    • http://saothienemb.com/uploads/images/files/jojeteginituwipubogabarik.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/jibimilejevipizabojuzojod.pdfIn PDF document text
    • http://www.nachtruhe.info/up/files/joduv.pdfIn PDF document text
    • https://cualuoihoanmy.com/uploads/userfiles/file/sazajipaveniv.pdfIn PDF document text
    • https://tekartltd.com/upload/files/12870904893.pdfIn PDF document text
    • https://ptogel1.com/contents/files/sanuraweposufi.pdfIn PDF document text
    • http://www.salpasafarit.fi/tiedostot/files/98080731584.pdfIn PDF document text
    • https://pointwebhost.com/calisma2/files/uploads/14186168555.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=my+hero+academia+season+5+ep+10+eng+subPDF 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_off0000dd3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD3F 11472 bytes
SHA-256: 89e26ecaafe5ee080c9500b66ad041fdd14ffff38846ad7a8abc7f3121ac8326
font_01_sfnt_off0000f7de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7DE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010ff0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FF0 18356 bytes
SHA-256: b48fe00392767371db645c91e6611c995d4a34ebb31eb6f8e87c2beb4da6b036