Malicious PDF — malware analysis report

Static analysis result for SHA-256 d7f37823c008e307…

MALICIOUS

PDF

80.6 KB Created: 2021-09-23 14:44:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 4f35ac4649afd2a4ec932bde89d0c80c SHA-1: 3237d0c8f6bb36064d6ec17443e046d05aa33f97 SHA-256: d7f37823c008e307b5028111fdf065d991ab0c0621e0a107cd064c483efcbaf1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm pointing to compromised CMS upload storage and disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the presence of embedded URLs and the nature of the link farm suggest the document is designed to trick users into downloading a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://kk-gorenjska.si/uporabnik/file/wapazolinibeda.pdf In PDF document text
    • http://nelly-design.ru/upload/files/49161240308.pdfIn PDF document text
    • https://medius.sk/userfiles/file/91231365361.pdfIn PDF document text
    • https://primer-spb.ru/files/files/pezarusopukeponokanaluxem.pdfIn PDF document text
    • https://hobbypet.cz/files/file/39580741437.pdfIn PDF document text
    • http://sieuthicayxanh.vn/webroot/img/files/80339114008.pdfIn PDF document text
    • http://yepuco.com/uploads/files/tubisuwuzadono.pdfIn PDF document text
    • https://www.comperat-89.fr/ckfinder/userfiles/files/tobeven.pdfIn PDF document text
    • http://inimtrento.it/userfiles/files/74731844813.pdfIn PDF document text
    • https://europacreativaeuskadi.eu/files/galeria/files/dotaparajiso.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/g11evss5ec1t0cm2f5825nlqts/pezavosejipofaludos.pdfIn PDF document text
    • http://eko-uklid.com/files/file/zatimuselugasusa.pdfIn PDF document text
    • https://kuraniterbiye.com/resimler/files/dakokipima.pdfIn PDF document text
    • https://familienbilstrup.dk/userfiles/file/bavadivopitesapili.pdfIn PDF document text
    • http://loscogliodifavignana.it/userfiles/files/23957139019.pdfIn PDF document text
    • https://spvi.cn/filespath/files/20210903231203.pdfIn PDF document text
    • http://rideabikenews.com/user_img/files/buwokakuvodabavuziguwu.pdfIn PDF document text
    • https://www.frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/dimejeg.pdfIn PDF document text
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/77b8b4a2b096fd72003774b0c881ee14/4804841545.pdfIn PDF document text
    • https://unicon-msk.ru/data/files/45161783974.pdfIn PDF document text
    • http://fajni3333.fun4two.pl/uploads/assets/file/40603389264.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b3902c6e6c---sasogomudajolabaj.pdfIn PDF document text
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/msrh0siar4m4uopqfjipl6k6i0/40292151330.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=poco+f1+gallery+apkPDF 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_off0000d852.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD852 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f064.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF064 17280 bytes
SHA-256: 96ec6fe786a04dbf2781d6c56288a22a4b18c7a9eeb6efc105f7d7e41735723e
font_02_sfnt_off00011d5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D5D 10452 bytes
SHA-256: 1e390c68578392df4082a657e2d537d9d130ce65f8e2f63840c23cdc92e0c403