Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4c87ca30b32e1d0…

MALICIOUS

PDF

75.6 KB Created: 2021-09-06 13:03:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: d8ef538a77694fdc5a3551f9cb3ebb2c SHA-1: 5d7050420fb8f51dad159770ba2b73888f97e7d2 SHA-256: a4c87ca30b32e1d0200258bbb9399c09c6e813dcef0f802e99434a508e71f4fc
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to potentially malicious or unknown domains, indicating a link farm or phishing lure. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of a phishing or malware distribution campaign, likely initiated via a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://couvreur-hautdoubs.fr/internet_new/images_et_fichiers//file/78607827813.pdf In PDF document text
    • https://www.pharmawell.eu/ckfinder/userfiles/files/dujiboseker.pdfIn PDF document text
    • https://www.multilandtours.com/assets/ckfinder/userfiles/files/razasofafezibikugukiva.pdfIn PDF document text
    • http://fotobambagiotti.it/userfiles/files/disozovupasupexulofisuvel.pdfIn PDF document text
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/c22d370317acbbdb749d9a4556ef104c/firulavegejerudobepalovo.pdfIn PDF document text
    • https://ph2020.org/FCKeditor/file/41208297123.pdfIn PDF document text
    • https://floridainvestment.cz/files/file/vifosi.pdfIn PDF document text
    • http://cosmoscm.com/contents/files/67518785426.pdfIn PDF document text
    • https://gbagencement.fr/uploads/file/58537243681.pdfIn PDF document text
    • http://fslawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/logolosepafelafosama.pdfIn PDF document text
    • http://esoftland.com/userfiles/file/merifov.pdfIn PDF document text
    • http://secretlove.ch/ckfinder/userfiles/files/xivatadawuvadijo.pdfIn PDF document text
    • http://call.ae/wp-content/plugins/formcraft/file-upload/server/content/files/1608d80b7e3929---vujowupabosotodomuv.pdfIn PDF document text
    • https://hoongnau.com/upload/files/46270959763.pdfIn PDF document text
    • http://fpsh1980.com/clients/7/7d/7de5299bd6bdc19cdd6b275c058e9c4a/File/nafesepiwanumegokataduxab.pdfIn PDF document text
    • http://zatoodesign.com/userfiles/files/15321625809.pdfIn PDF document text
    • https://jesssmithtri.com/jesssmith/ckfinder/userfiles/files/69146015997.pdfIn PDF document text
    • http://falerisztika.hu/tmp/34999846021.pdfIn PDF document text
    • http://baaningdoi.com/file_media/file_image/file/49653525413.pdfIn PDF document text
    • https://brianhigbielaw.com/UserFiles/file/7483439048.pdfIn PDF document text
    • http://gujaratbusinesspages.com/userfiles/file/masub.pdfIn PDF document text
    • http://gernano.eu/gfx/userfiles/files/rirederututelitidifaxonov.pdfIn PDF document text
    • http://livelyway.com/ckfinder/userfiles/files/7440341443.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=laudate+omnes+gentes+pdf+taizePDF 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_off0000c355.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC355 17812 bytes
SHA-256: f04d0793e88d69a590e08ad1555b7c16f95066d0145e65206b4556d2618aae06
font_01_sfnt_off0000f065.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF065 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001087c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1087C 10812 bytes
SHA-256: d887a9147f9994ec034822be701b4422a0d17591bb1c7cef22bcc00d902f5919