Malicious PDF — malware analysis report

Static analysis result for SHA-256 f85f561d94ef6e2d…

MALICIOUS

PDF

83.7 KB Created: 2021-09-11 16:38:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: fb9652654abe9f0543ff193012523d8c SHA-1: 48441496b46b3345ef9718f7e0a13713239153c7 SHA-256: f85f561d94ef6e2d5304b48265f9b927cf30223d257bd4a87056e4dbcf2fca7c
134 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also contains numerous external URIs, many of which point to potentially compromised websites hosting PDF files, suggesting a link farm or redirection mechanism. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://jezirka-biobazeny.cz/UserFiles/File/gofemamo.pdf In PDF document text
    • http://krishikhabar.net/assets/ckfinder/core/connector/php/uploads/files/pokunonozatoriwux.pdfIn PDF document text
    • http://artin-intranet.com/ckupload/files/41269013061.pdfIn PDF document text
    • https://prokoncept.hu/admin/blogfck/image/file/povijufulavumawimodezu.pdfIn PDF document text
    • https://www.alitec.es/js/ckfinder/userfiles/files/16972876051.pdfIn PDF document text
    • http://mebel-moscow.com/content/xuploadimages/file/towudebolejidesupopuvug.pdfIn PDF document text
    • https://greenline.bg/userfiles/file/bupunugomasununu.pdfIn PDF document text
    • https://bonekarusa.com/contents/files/41991644714.pdfIn PDF document text
    • https://beldapin.com/calisma2/files/uploads/pigixeduvopiri.pdfIn PDF document text
    • http://pm-property.pl/userfiles/file/66073906084.pdfIn PDF document text
    • http://www.hangmandigital.com/files/file/97647192976.pdfIn PDF document text
    • https://emprenderem.cl/files/mewodujavoserulibom.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613b0d555dc44---50326683639.pdfIn PDF document text
    • http://droprint.my/home/ququ4923/public_html/userfiles/file/penarijonotuditupeg.pdfIn PDF document text
    • http://terezszilvia.com/images/uploaded/file/zawevanesakavuzelajusigad.pdfIn PDF document text
    • https://drproperty.in/userfiles/file/fesobigukagelujufesaw.pdfIn PDF document text
    • https://muahohangnhat.com/app/webroot/uploads/files/58011054680.pdfIn PDF document text
    • http://helderlive.nl/ckfinder/userfiles/files/92088968225.pdfIn PDF document text
    • http://speckletrack.com/update/editor/file/67725152051.pdfIn PDF document text
    • http://taiwan-casters.com/userfiles/file/63091625236.pdfIn PDF document text
    • http://polskienarty.pl/data/aktualnosci_imgs/file/sileduzexuxowijovipoguw.pdfIn PDF document text
    • http://bonaparte-kerkrade.nl/fckeditor/ckfinder/userfiles/file/bizunizadi.pdfIn PDF document text
    • http://aihyang.com/userfiles/file/50637711038.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=dragon+ball+z+season+5+episode+2PDF 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_off0000d4e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4E4 10924 bytes
SHA-256: 2348f111440e586f1911dc47c83a1af384589a5cb0879a11089044dcdf1cf905
font_01_sfnt_off0000eded.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDED 22496 bytes
SHA-256: 345f0dbb3ead603b87bf13246c2ae5eb8aa1cb088766c8b2d01fecef290c23ef
font_02_sfnt_off0001293c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1293C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1