Malicious PDF — malware analysis report

Static analysis result for SHA-256 035157c5aaba4816…

MALICIOUS

PDF

83.1 KB Created: 2021-09-14 08:07:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 87b1bdf7e7fb1605eb5a79566e5bc9c9 SHA-1: 18116c9c4c7cb7f803e266886b80cae30aae7ca8 SHA-256: 035157c5aaba48161bc7d1ff51fafa95ec69a47cf02fffe7931b68593336a78e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple compromised CMS upload links further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://stisk.com/file/2298895300.pdf In PDF document text
    • http://marinaxaraes.com.br/ckfinder/userfiles/files/70431319889.pdfIn PDF document text
    • https://lalicorne-hotel.com/userfiles/file/jivuzifimatuwemufari.pdfIn PDF document text
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161357e38625fd---39436179502.pdfIn PDF document text
    • https://onlineadda.net/ckfinder/userfiles/files/74283835690.pdfIn PDF document text
    • https://redengewinnt.com/userfiles/file/17804163481.pdfIn PDF document text
    • https://china-glass-mosaic.com/userfiles/files/20210913_161706.pdfIn PDF document text
    • http://kfnmsz.com/upfolder/e/files/20210904015735.pdfIn PDF document text
    • http://doks-films.com/pcms/content/file/fizataferanapibibujaso.pdfIn PDF document text
    • https://nikoljski.com/ckfinder/userfiles/files/34556186830.pdfIn PDF document text
    • http://xn--80aap0abfiql8h.xn--p1ai/admin/ckfinder/userfiles/files/89437467722.pdfIn PDF document text
    • http://maiodi.com/userfiles/files/31951765595.pdfIn PDF document text
    • http://phuvuongcorp.com/luutru/files/kegise.pdfIn PDF document text
    • http://qishuochem.com/siicea/userfiles/file/97359517576.pdfIn PDF document text
    • https://atiksigorta.com/files/97568266184.pdfIn PDF document text
    • http://dwornawodzie.pl/userfiles/file/21781203796.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/1613098c51827b---61550251401.pdfIn PDF document text
    • http://baihsad.com/userfiles/files/20210907_163439.pdfIn PDF document text
    • https://eguiders.com/uploads/694042669.pdfIn PDF document text
    • http://ecolservizinettuno.com/userfiles/files/89509479957.pdfIn PDF document text
    • http://alhegazgroup.com/userfiles/file/madakivugimezovepamuxi.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/d9269fead9b9ea1ed92d656a0390413f/ruzexudimoraxak.pdfIn PDF document text
    • https://psg66.ru/admin/ckfinder/userfiles/files/29912294723.pdfIn PDF document text
    • http://reckdance.pl/userfiles/file/tudowasakolereku.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=accidentally+deleted+text+messages+androidPDF 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_off0000dc2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC2D 18600 bytes
SHA-256: c3ae7b4add3e1ba8f01c12fa593d81f148eb9b92844b5b9e92d628b2d7554b6f
font_01_sfnt_off00010ce8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CE8 10912 bytes
SHA-256: 35ca939468c6286331f38e57fd89867b1e93f44828a2516cecb210ce9f228766
font_02_sfnt_off00012605.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12605 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1