Malicious PDF — malware analysis report

Static analysis result for SHA-256 b051e325c41fb4f6…

MALICIOUS

PDF

82.4 KB Created: 2021-06-30 20:09:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 597e983359c6443429e03f5d84079f12 SHA-1: dfa8c9584f1c01e085721ab817c5ec3f5fd5d331 SHA-256: b051e325c41fb4f61e75d615ab650f2cd5a3cf38931288a1e8063e2650eb339f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs, many of which point to compromised CMS uploads and link farms on disposable hosting, suggesting an attempt to obscure the final destination. While no scripts were directly extracted, the nature of the embedded links and the 'link farm' heuristic strongly suggest a phishing or redirection attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/u02m921dc9t4c0qqqoi8ivoami/kexasemojete.pdf
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/52298744930.pdf
    • http://logiccpacma.com/ckfinder/userfiles/files/19154113361.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/89fki70r3t313vevhdl3rrtbh2/gibides.pdf
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160afcd167246e---xizofuvisuwilinumu.pdf
    • http://boeschfamilytravels.com/clients/43210/File/6552911356.pdf
    • http://15889163.com/ckupload/files/ruxugibisilekitab.pdf
    • https://thejasmineway.net/wp-content/plugins/super-forms/uploads/php/files/quc140uim0ncq20969eplt0bk3/pebukixejebudirabewo.pdf
    • https://www.letspassdriving.co.uk/wp-content/plugins/super-forms/uploads/php/files/u7hqsslaph4vam0chha5f1t1d3/88996911254.pdf
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160b4bff57d223---93419269087.pdf
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/h41775l1l3ufnkulrhhefpbrjj/gabof.pdf
    • http://aceonlinementors.com/userfiles/file/pogofisipototivegodamenuz.pdf
    • http://a-kamen.com/userfiles/file/91529925078.pdf
    • https://vestol.bg/files/file/piwumedilutetuwapoz.pdf
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2a602d6082---nevixofabetimoxu.pdf
    • http://metamorfoza-krosno.pl/userfiles/file/bonat.pdf
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf4e11737e3---598392945.pdf
    • http://a-daily.jp/app/webroot/contents_img/files/82429597566.pdf
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160baed116b275---19529988405.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=practice+b+factoring+ax2+bx+c+answers
    • 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_off0000de78.bin
2d3471bcc68d50218b5eb0fd89a184bfbe6d22b2cd5a7dec3193b518b1c1a0e7
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE78 17248 bytes
font_01_sfnt_off00010b0e.bin
58e0f404ace013b92350b02c41136719ab386251deedbf57501aa84b1f645e5c
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B0E 10916 bytes
font_02_sfnt_off000124a3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x124A3 16792 bytes