Malicious PDF — malware analysis report

Static analysis result for SHA-256 2542b1731a931caa…

MALICIOUS

PDF

78.6 KB Created: 2021-10-05 15:09:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 3f6b57c47a48f603cec34b163bbe3f6b SHA-1: 50f37502306f4a71d771fc61af9c04ca4ce504f9 SHA-256: 2542b1731a931caa07d2a53d845c530649840a4a517167a4afcea2c43de5da78
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm pointing to multiple domains, many of which are hosted on disposable infrastructure or compromised CMS uploads, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or serving a secondary payload. No scripts were extracted, but the PDF structure and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 https://atiksigorta.com/files/4868052351.pdf In PDF document text
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615297911901e---81162359464.pdfIn PDF document text
    • https://sledovani.gpshlidac.cz/www/userfiles/files/5775586055.pdfIn PDF document text
    • http://fittbikese.hu/files/file/54122781378.pdfIn PDF document text
    • http://thegioixedap.net/upload/files/fuwiw.pdfIn PDF document text
    • http://zhongjiukeji.com/upload_fck/file/2021-9-19/20210919084451752664.pdfIn PDF document text
    • https://betalinktech.com/blmedia/file/40225976363.pdfIn PDF document text
    • http://gesundimjob.at/images/content/files/96487526318.pdfIn PDF document text
    • https://hkparkkonutlari.com/image/files/41518380399.pdfIn PDF document text
    • https://saleskerala.com/ckfinder/userfiles/files/93108003039.pdfIn PDF document text
    • https://suprizpin.com/calisma2/files/uploads/4891654699.pdfIn PDF document text
    • http://csim.jp/ckeditor/uploads/files/wugedol.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/tvtrhb2qekpbgauuhi2c3o7opr/fujeno.pdfIn PDF document text
    • http://mecateengenharia.com.br/ckfinder/userfiles/files/51145576596.pdfIn PDF document text
    • https://sandipkumardutta.com/ckfinder/userfiles/files/tiwinezozimikudit.pdfIn PDF document text
    • http://thecargonepal.com/userfiles/file/mavogupobod.pdfIn PDF document text
    • http://lacasedescaraibes.fr/file/nanobegalavakojifof.pdfIn PDF document text
    • http://tpt.taipei/asset/uploads/files/kevawunibigatosonujul.pdfIn PDF document text
    • http://kuhomania.ru/ckfinder/userfiles/files/20770991525.pdfIn PDF document text
    • http://yomamasushitogo.com/uploads/files/10213457646.pdfIn PDF document text
    • http://youil.org/userData/board/file/71042154291.pdfIn PDF document text
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/161534b50ea953---kevapajutapukukoxaf.pdfIn PDF document text
    • https://mbzl-pro.xyz/web/img/podborky/files/99790831024.pdfIn PDF document text
    • https://tasleemdubai.com/userfiles/files/guzafidif.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=ideal+temp+for+hot+water+heaterPDF 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_off0000d11f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD11F 17092 bytes
SHA-256: 87ff8794a36905a2a1c37f7b9509c5da87ecd2f2651cd16a1e54ecac17cdb736
font_01_sfnt_off0000fd49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD49 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011560.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11560 10436 bytes
SHA-256: b19a92c149d7a96fd3c5eff7cb259f7b102623c5cfbad50867efd9bfbad2d42e