Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7fda4eb637f9d92…

MALICIOUS

PDF

80.3 KB Created: 2021-09-14 05:02:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 256f3d1069f4e361fa772aac1b0b48a8 SHA-1: 0c46e0b573dd005df1f469e8e519a4598770570b SHA-256: a7fda4eb637f9d928b6aced2bc91947a89ddd9ec13b00619ee5945881dfe2f64
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS uploads or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://locktactyuma.com/ckfinder/userfiles/files/40147433484.pdf In PDF document text
    • https://toananhmedical.com/uploads/files/sexarivemisaxogavob.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/161311eddbb930---sozugeferu.pdfIn PDF document text
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/18ac100e5a69cd55a35f14c167ab1683/xaponit.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1613fcfb2a202e---25487641765.pdfIn PDF document text
    • https://abyway.lv/images/ck_images/files/32683407449.pdfIn PDF document text
    • http://puzynowska-kancelaria.com/userfiles/file/veralakopazut.pdfIn PDF document text
    • http://larrysiegellaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/selurujogi.pdfIn PDF document text
    • http://dribblebar.pl/userfiles/file/ponuturuvisevep.pdfIn PDF document text
    • http://rosniyom.com/userfiles/files/40954600517.pdfIn PDF document text
    • https://bikeid.net/ckfinder/userfiles/files/753118534.pdfIn PDF document text
    • http://sportschoolindex.nl/images/uploads/36060977891.pdfIn PDF document text
    • https://sambelteri.com/contents/files/liviwarumidizu.pdfIn PDF document text
    • http://nattuvaartha.com/assets/ckfinder/core/connector/php/uploads/files/40106322167.pdfIn PDF document text
    • http://orlickachata.cz/files/files/gamuzimizopufifexotimivom.pdfIn PDF document text
    • https://eccdc.org/application/webroot/userfiles/file/86370184284.pdfIn PDF document text
    • https://roshnaai.com/ckfinder/userfiles/files/xidukexibiwoloxabok.pdfIn PDF document text
    • https://discovery99.com/userfiles/file/relupakezepubonegibaz.pdfIn PDF document text
    • http://www.smartlandgroup.com/ckfinder/userfiles/files/wowuko.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135ba9906ad3---62746975746.pdfIn PDF document text
    • https://roshnaai.com/ckfinder/userfiles/files/62986961618.pdfIn PDF document text
    • http://mkbeauty.vn/luutru/files/farejoro.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=remote+ndis+based+internet+sharing+device+missing+windows+7PDF 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_off0000d20f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD20F 18040 bytes
SHA-256: 90312a9e902b8fae50d3a63d27b47b592dda3bac45a72b7a32fefef8bc6cbba1
font_01_sfnt_off000100d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100D9 11160 bytes
SHA-256: 0c96e2fcc1e0b1ac73417d26cfb9e3324f360a43ec49660e44d816762d50f1c9
font_02_sfnt_off00011ab0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AB0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1