Malicious PDF — malware analysis report

Static analysis result for SHA-256 819f9c82d1b5fc59…

MALICIOUS

PDF

78.5 KB Created: 2021-07-17 20:58:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: f667ebfe35165add166b5877b941286f SHA-1: 61c72586542db1b7662e41e748ea7a23e6da3fa8 SHA-256: 819f9c82d1b5fc59efbd0f3963b1322d7d1c1eac2cb0b51caba86a505cb3a676
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The file contains numerous links pointing to compromised WordPress upload directories and disposable hosting, indicating it functions as a link farm. The primary purpose appears to be directing users to malicious sites, likely for phishing or to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a7d76de8d7---71101116253.pdf In PDF document text
    • http://daivupaint.com/img-chamthi/files/62067322863.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ac1316b5351---xotuxebosub.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607fa20d5180f---12575294252.pdfIn PDF document text
    • http://altaprecision.com/userfiles/file/dewafakuzuvevoxuje.pdfIn PDF document text
    • https://protechlighting.com/wp-content/plugins/super-forms/uploads/php/files/cbdc2a1cab394c80f22dda798bf38a87/19067936223.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077d537bd17d---luzobefopugat.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/9r2fqhfhvecdb7oga827l0qdu2/41115777690.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160aae63bdc359---47112098874.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16085e666e4b9e---resezoxujogefulaperalep.pdfIn PDF document text
    • https://medicinasolidale.org/wp-content/plugins/super-forms/uploads/php/files/65dd7e4bc96d30c08f6e03e364db2b27/lefemi.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/d38438f67b2b2dd0bdafae9ea969b210/potukezo.pdfIn PDF document text
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/r0pi5iettm0m9pirnufnlphneq/zujim.pdfIn PDF document text
    • http://gramercy-grand.ru/files/file/jusazewola.pdfIn PDF document text
    • https://jxloanchien.com/style/postimage/file/kidemapelofomagimiwig.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/816ca8e09fb19ee08fbf32d75bc6f9b5/sanolilobitot.pdfIn PDF document text
    • https://fotobolfestmeny.hu/mvc/userfiles/file/98244373705.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b067071bf80---19101422004.pdfIn PDF document text
    • http://au-zlato.sk/upload/files/mawufifowejemafifagaxe.pdfIn PDF document text
    • https://www.oneirishrover.com/wp-content/plugins/super-forms/uploads/php/files/9a9f22394b40ce00f3f825b21a86ea8b/84931334351.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/f80eb67dfa548360cfcdba17c5a45906/burigagavozupupegiparurov.pdfIn PDF document text
    • http://polskienarty.pl/data/aktualnosci_imgs/file/kazajux.pdfIn PDF document text
    • https://paperland.bg/uploads/file/77529134893.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc976b145fb---16729961732.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=words+with+tious+and+ciousPDF 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
stream_003_off0000fb78.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0xFB78 10468 bytes
SHA-256: f1c3ad16820b9118efb63adbb95c55b22fe838938e9379d04ba7a3c3bf62278f
font_00_sfnt_off0000cde9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDE9 17616 bytes
SHA-256: 0af17ae69fd84a46ebd0b9811cb89f653fadd3ec19f38f08d20af547fb8f9148
font_02_sfnt_off00011347.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11347 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1