Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4f70b804a41a73c…

MALICIOUS

PDF

85.9 KB Created: 2021-09-20 17:48:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 89425e83b95612714f16709e9842c7df SHA-1: 0180e5054d6ff2bb11ad8f97be08b6f3b7f38788 SHA-256: b4f70b804a41a73c872bef4ccc2b1a452ed994a3ea9b8307e681da69905482ff
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress upload directories or other potentially disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The document body is unreadable binary data, suggesting it's not intended for direct user consumption but rather to host the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 https://madspot.dk/ckfinder/userfiles/files/nukuzuzu.pdf In PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613efea9365ce---gaselopijokobilazejetadig.pdfIn PDF document text
    • http://zhfangyuan.com/uploadfiles/files/79392978511.pdfIn PDF document text
    • http://ametansk.ru/uploads2/55096456918.pdfIn PDF document text
    • https://traveletrust.com/basefile/traveletrustcom/files/96152112909.pdfIn PDF document text
    • https://psihodesk.ro/ckfinder/userfiles/files/75802216831.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/p953klprjkvvltdaf43nu9hut1/watovifozufewanogoxeb.pdfIn PDF document text
    • http://vitali-schulz-eiskunstlaufen.de/userfiles/files/vuboxonap.pdfIn PDF document text
    • https://panificioilcavaliere.it/userfiles/files/93711337008.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/d55165380c648d713a8e5e1fb988be2c/54697422832.pdfIn PDF document text
    • https://saksisan.com/upload/ckfinder/files/dirisitugalo.pdfIn PDF document text
    • http://ct-tci.com/cttax/userfiles/files/96362883654.pdfIn PDF document text
    • http://purofirstli.net/userfiles/file/53454723819.pdfIn PDF document text
    • https://ibericadearmerias.com/file/kejurozusedodekedo.pdfIn PDF document text
    • http://ciaomamma.hu/editor_up/80669480343.pdfIn PDF document text
    • http://mtsskzy.com/userfiles/file/23590698153.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145d33241854---morod.pdfIn PDF document text
    • http://rockhouseschool.com/rockhouse/uploads/files/xubimezopejelonefiva.pdfIn PDF document text
    • http://schroniskoorzechowce.pl/ckfinder/userfiles/files/gunolikosizabujo.pdfIn PDF document text
    • https://aecvfcom.nrgence.com/upload/userfiles/files/vidiwoxuk.pdfIn PDF document text
    • http://ctm.it/userfiles/file/gituduboxorofuw.pdfIn PDF document text
    • https://zebcom.in/userfiles/file/jedesilipogog.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=machine+learning+for+dummies+pdf+downloadPDF 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_off0000e867.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE867 18196 bytes
SHA-256: 96304e4c784cf2a23948fd1aad57074a74f336536c5b39938ec1d571460184b3
font_01_sfnt_off0001179b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1179B 11148 bytes
SHA-256: 81a217228421d1de175bf9bdd10770dcc43ae653879c2966f768d41e6615adff
font_02_sfnt_off0001314d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1314D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1