Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc91e3f1efb7cc1e…

MALICIOUS

PDF

73.0 KB Created: 2021-09-16 00:06:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 6883e97e1525dcce1b011ea166f4ca16 SHA-1: 6d344a2a3d0305edefb77f67ad5d5af8d7276128 SHA-256: dc91e3f1efb7cc1ed8cac9a526778123ad58836dfc7d4eaaa2ee18da857cb046
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on compromised CMS platforms, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to exploit users by directing them to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161425fc11fb06---dotaresag.pdf In PDF document text
    • http://xn--42cfa4ewb0a0b3fwh.com/imageupload/files/radovugudonime.pdfIn PDF document text
    • http://athaj2.specialty-match.com/upload/files/68669683615.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161356fee306d5---vobobelapesabom.pdfIn PDF document text
    • https://iwanbim.com/userfiles/files/8687334170.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/71816937351.pdfIn PDF document text
    • https://seltec.io/images/uploads/files/21652842748.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138d191c77a7---60457872205.pdfIn PDF document text
    • https://sacc-la-chaux-de-fonds.ch/fichiers/file/86644462165.pdfIn PDF document text
    • http://freeware-software-download.de/uploads/editor/file/67589414173.pdfIn PDF document text
    • https://xn--80aaa1arbfjoe3bzh.xn--p1ai/data/files/sepusuzegawewuzosuwagu.pdfIn PDF document text
    • https://xebecdesign.com/xebec/userfiles/file/96737804234.pdfIn PDF document text
    • http://dmkert.hu/files/file/mumotuxuvadinusofipen.pdfIn PDF document text
    • http://hunicorn.hu/userfiles/file/16709231152.pdfIn PDF document text
    • http://latiendasegura.com/contable_prueba/userfiles/file/feziximem.pdfIn PDF document text
    • http://ankaraeksioglu.com/resimler/files/61307758012.pdfIn PDF document text
    • https://relaxbotanika.cz/ckfinder/userfiles/files/31708984648.pdfIn PDF document text
    • http://rasciindia.com/firetech/ckupload/files/77292756329.pdfIn PDF document text
    • https://volnynaklad.cz/data/file/2637978573.pdfIn PDF document text
    • http://yevres.fr/ckfinder/userfiles/files/sitipezibu.pdfIn PDF document text
    • http://scsychem.com/upload/files/debilekiza.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/161426022275f8---96780669663.pdfIn PDF document text
    • http://litho-and-co.fr/ckeditor/upload/files/xamosawiladotuvuxijige.pdfIn PDF document text
    • https://xn--22ck6bdp5cach0mc23a.com/ckfinder/userfiles/files/22858063425.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=house+rules+watch+onlinePDF 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_off0000bc3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC3B 16512 bytes
SHA-256: 5258bcc30995acddf4b759a6415c52fff644e790c69687de31f94e2d031f979a
font_01_sfnt_off0000e6dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fef3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEF3 10504 bytes
SHA-256: 60c1c4a4f12365ea00451d6362f4b025889e677adbbea9a05667ac295f3643d3