Malicious PDF — malware analysis report

Static analysis result for SHA-256 dd84b531dff7718f…

MALICIOUS

PDF

82.3 KB Created: 2021-09-15 22:14:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a8d0c002db96e4ce7d5d034c99725a79 SHA-1: f34095902ade7c55062301a96a11e1dc47cbd733 SHA-256: dd84b531dff7718f3525a846e14b5de451b8b604fe2cee665b60b9bd3c92dfa6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link T1059.007 JavaScript

The PDF contains numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a deliberate attempt to create a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://queure.ru/uplcv?utm_term=dual+boot+android+windows+7
    • http://phuongsen.com/img-chamthi/files/14558012133.pdf
    • https://stmpallet.com/ckfinder/userfiles/files/bebobojud.pdf
    • http://soles2walk.cz/data/file/birosifewinoxoledat.pdf
    • https://jlgardner.org/home/jlg/public_html/ckfinder/userfiles/files/fivojubukezivewivofavu.pdf
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f92fe887dd---92446921965.pdf
    • http://fratellibeninca.com/images/file/bozuzifuj.pdf
    • https://dailyhondaotomientay.com/upload/files/85785131916.pdf
    • http://china-engine.net/ckfinder/userfiles/files/32227651092.pdf
    • https://52fantasies.com/home/holly/public_html/ckfinder/userfiles/files/43562432672.pdf
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/qkgbcpusrijbjhmfho32o2v8h6/97690448844.pdf
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161316221d4815---79931487453.pdf
    • https://interangkorcondominium.com/userfiles/file/44017499314.pdf
    • http://scuolascifondocortinadolomiti.it/userfiles/files/1843610829.pdf
    • https://soechi.id/userfiles/file/32917157037.pdf
    • http://sgrappresentanze.eu/userfiles/files/5154271359.pdf
    • http://rybarict.cz/webpagebuilder/ckfinder/userfiles/files/79069877824.pdf
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16132c8acd30b9---856656421.pdf
    • https://dehayemek.net/upload/ckfinder/files/67626134714.pdf
    • https://franchiseharbor.com/files/files/90810411567.pdf
    • http://thechelseaff.com/user_uploads/files/fakexitano.pdf
    • http://sieuthibongda.net/ckfinder/userfiles/files/64475108666.pdf
    • http://club-integra.ru/userfiles/file/812803167.pdf
    • https://isuzuphonoi.com/data/dulieu/files/52660698952.pdf
    • http://dautuck.com/uploads/userfiles/file/mifebep.pdf
    • http://jinsonmetal.com/Upload/file/51048291138.pdf
    • 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_off0000dd49.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD49 16792 bytes
font_01_sfnt_off0000f560.bin
b6c7ac1d6971e943f83ac6a6b863fedbc65d2a5a3c2e3445ebcc8587ccb1ce03
pdf-font-stream PDF embedded font (sfnt) at offset 0xF560 10488 bytes
font_02_sfnt_off00010d62.bin
85c6fa8a02b6a5356bd1a2adec4d3a4228c165f6917a14e64efe143ae21623eb
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D62 17988 bytes