Malicious PDF — malware analysis report

Static analysis result for SHA-256 2725db0a91f0c660…

MALICIOUS

PDF

87.2 KB Created: 2021-09-18 19:35:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 726314bee967fbd86fba35592f1747a5 SHA-1: 6688b72e01cf1782bba6fd1b838b0b924ef5a937 SHA-256: 2725db0a91f0c6600195cfe937c9ff1057caf8e186c7155aad50838bfaecf015
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous links to external websites, many of which host other PDF files, suggesting a link farm or redirection mechanism. The 'SE_CALLBACK_LURE' heuristic indicates the document's content is designed to trick users into calling a phone number for support or to resolve a fake issue. While no scripts were directly extracted, the presence of embedded URLs and the ML classifier's high confidence score point towards a malicious phishing or scam attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 7

  • 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.
  • 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 https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/c8a74ae2d4d6d3d1f246f03dfad27cc3/kesuzusazeraba.pdf
    • https://aglogistics-bo.net/userfiles/file/25335585224.pdf
    • http://appli-veolia.net/ckfinder/userfiles/files/natenebodezofi.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16136b782150fb---94152194991.pdf
    • http://basar-hemeringen.de/ablage/userfiles/files/gezaledoredojavifomov.pdf
    • http://stowarzyszeniemalyksiaze.eu/img/upload/files/18714169408.pdf
    • https://www.afoa.org.ar/backend/ckfinder/userfiles/files/93041918023.pdf
    • https://phunhai.net/upload/files/28997167157.pdf
    • https://la-klamm.org/Files/files/disomuvubiba.pdf
    • https://skillmapmagazine.com/ckfinder/userfiles/files/ledefukufuzulovazugunovor.pdf
    • http://krr-nfe.com/suratnfe/UserFiles/File/24661454983.pdf
    • http://moscowballet.ru/userfiles/file/97386882305.pdf
    • http://tianfonmm.com/d/files/biwixunumonupupemuxugur.pdf
    • https://metnar.pl/web/uploads/files/60602750661.pdf
    • http://elpijisystem.com/file/vomenowilu.pdf
    • http://perfekt-dom.pl/designhome/admin/userfiles/file/1278389342.pdf
    • http://bigbazar.cz/is/images/FCKeditor/File/18435097806.pdf
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161312d8978ce0---peninipoma.pdf
    • http://hytechplus.com/userfiles/file/sewabude.pdf
    • http://kxxbs.com/uploadfiles/file/a/novigiwumo.pdf
    • http://conganbacgiang.vn/app/webroot/uploads/files/16718104367.pdf
    • http://www.como-grup.ro/fisiere/file/satimumegowujaj.pdf
    • http://abw10thstreetne.com/uploads/files/17520254550.pdf
    • http://hocomesun.com/upload/wozususokeloribor.pdf
    • http://paddockj.com/user_data/editor/ckfinder/core/connector/php/upload/files/18344852302.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=rndis+driver+usb+tethering+windows+xp
    • http://perfecturology.cafe24.com/upload/editor/imagefile/31865531161.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_off0000ea58.bin
1307dab7d8464a247af86e1debd24525c2c9edba3829fff953f5e128b8560a4a
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA58 11000 bytes
font_01_sfnt_off00010385.bin
27dbab43bd4e67f8baa399635ce3604f88b589424e047c5ecf0a886cbdebfef6
pdf-font-stream PDF embedded font (sfnt) at offset 0x10385 19448 bytes
font_02_sfnt_off0001365e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1365E 16792 bytes