Malicious PDF — malware analysis report

Static analysis result for SHA-256 1623c33f2f1db890…

MALICIOUS

PDF

84.7 KB Created: 2021-07-05 16:48:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fb3d47c2cc0d3c4a7c9b51774b02c8b5 SHA-1: 1e4ea544870e100de06a047b5aa3457ee70bd3cb SHA-256: 1623c33f2f1db890d3b084a10effc68be7014120d621ebd681b830c22b6dadb5
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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.
  • 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://xn--knstlerische-biografie-arbeit-lbd.ch/userfiles/files/wunuwetes.pdf
    • http://albarossa.jp/js/upload/files/lufarinetozozuv.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079c00619fc8---jigemutit.pdf
    • http://webelievedin1984.com/clients/6/67/676624d6593aa512bfa6e10e765af00e/File/laturutose.pdf
    • http://llux.vn/uploads/files/82417783264.pdf
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/a7gp91cvroak00f6qe6h191987/8481186921.pdf
    • https://appchecar.com/ckfinder/userfiles/files/69540397883.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1055da6e7---putem.pdf
    • http://didaconcept.com/admin/fckeditor/file/deroguwokilulegibawaki.pdf
    • https://luminex.pl/upload/file/20747869507.pdf
    • https://apparel.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/9a6900d00c6e76613b39c1c4a8a72dbc/poxaletiwen.pdf
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607c6d9614e67---60626269848.pdf
    • https://amrapalispot.com/userfiles/file/47881621518.pdf
    • http://www.kickcommerce.com/userfiles/file/veremuvujekitifodezulusi.pdf
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d185373cc4f---suvuxopufir.pdf
    • http://kpotplace.com/uploads/files/98281392046.pdf
    • http://curry-box-deluxe.de/userfiles/file/pizuzeloxonoporotuvato.pdf
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608023813454d---pefadunatezofe.pdf
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/ab2f9be3f5b6a9f2e5a79a7bd86ac495/32828430799.pdf
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/1609ac0409cb7a---48713395982.pdf
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/160710314a3bac---sibibafewo.pdf
    • http://phillipwhiting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c221c046be5---milidefusutonugajikusiraf.pdf
    • https://precisionautoandac.com/wp-content/plugins/super-forms/uploads/php/files/b8d6dbaa3deb2946e91dc3b8aaf28d9d/23942296925.pdf
    • https://morethancleaningservices.com/wp-content/plugins/super-forms/uploads/php/files/bde87cf8aa0588385d144e70d0f05a86/xazogosipetemadirak.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=how+to+make+someone+admin+on+minecraft+server
    • 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_off0000e673.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE673 16792 bytes
font_01_sfnt_off0000fe85.bin
43638f00c6066785e1146958ebf40ce529fd55af05e1df66e37db660ac98b07e
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE85 17360 bytes
font_02_sfnt_off00012c42.bin
404c4c44579137d9e2183262d5e95d3e10d981bdb9cfccb571342a04b4b6843a
pdf-font-stream PDF embedded font (sfnt) at offset 0x12C42 10828 bytes