Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf6e1a3712cbab75…

MALICIOUS

PDF

70.3 KB Created: 2021-09-25 05:01:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fecf57bec20178d48e0763e9bd35068e SHA-1: 36c427afa068812e046b97620eb54d87dbca890f SHA-256: cf6e1a3712cbab75bc927a7885680c18e6562fdd0ac95024f0f0863a66f40f97
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded URLs, many of which point to disposable hosting or compromised CMS uploads, suggesting a link farm designed for phishing or malware distribution. The ClamAV detection and ML classifier strongly indicate malicious intent. Although no scripts were explicitly extracted, the nature of the URLs and the PDF structure suggest it is designed to lure users into clicking malicious links, likely as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://heichapuzi.com/uploadfile/file/91936191360.pdf
    • http://c-amc.com/upload/files/22092781271.pdf
    • https://ariaparvaz.com/basefile/ariaparvazcom/files/12781456165.pdf
    • http://asv-solnice.cz/_files/file/54069636875.pdf
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130265b69da3---34644767306.pdf
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/4b69be443e29be2456bb4569d6a9dfa5/tulodof.pdf
    • http://alfamar.travelshops.pl/userfiles/file/pefonulu.pdf
    • http://biplano.eu/userfiles/files/39207530817.pdf
    • https://estoniapools.com/contents/files/89516602084.pdf
    • https://at1apigroup3.com/contents/files/88684719734.pdf
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161392f805bb97---56385677042.pdf
    • http://hcstonetw.com/uploads/files/202109221512308746.pdf
    • https://stka.gr/ckfinder/userfiles/files/kusis.pdf
    • http://fullx.net/files/juboraberoxotinafup.pdf
    • http://bulmarconsult.com/files/zafojexegepavusifi.pdf
    • https://svenjakretschmer.com/ckfinder/userfiles/files/66117321195.pdf
    • http://autobedrijvenindex.nl/images/uploads/movatutiv.pdf
    • https://sakesushimn.com/userfiles/files/jajefu.pdf
    • https://www.supremecaravans.com.au/application/third_party/ckfinder/userfiles/files/29429169414.pdf
    • http://a1-automotivegroup.com/upload/files/68845248435.pdf
    • https://bharatiyabhashaparishad.org/ckfinder/userfiles/files/sazotes.pdf
    • http://domainecomps.com/documents/files/25439062814.pdf
    • http://vncdata.net/app/webroot/uploads/files/8815138927.pdf
    • http://houselandia.ru/files/kuvosadoruti.pdf
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/ce36751f0d1f67bfc9e7378c6ef6b0b7/sagelofen.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=bollywood+movies+free+download+sites
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b396.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB396 16792 bytes
font_01_sfnt_off0000cba8.bin
0210d9f09ed581204d9f2832b03ca478ea88e32a4f9d4b17ee6c25ba27fe5034
pdf-font-stream PDF embedded font (sfnt) at offset 0xCBA8 15652 bytes
font_02_sfnt_off0000f203.bin
dd661cbaee746392ee3e32bd8e2c105afdb6279cee5a77a7a3631f908689888f
pdf-font-stream PDF embedded font (sfnt) at offset 0xF203 10836 bytes