Malicious PDF — malware analysis report

Static analysis result for SHA-256 2423f16249bc52a7…

MALICIOUS

PDF

87.2 KB Created: 2021-09-21 06:50:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 54ee5032831ef9a7d832fe0615bdf172 SHA-1: 679c26dde3379a3a78cc6befac3244b7e04fc2e3 SHA-256: 2423f16249bc52a74e1c7073c50cc42d28779452f721fcca78e740135caed876
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or malware distribution intent. It functions as a link farm, containing numerous embedded URLs that point to potentially compromised websites or disposable hosting. The presence of external URIs and link farm heuristics strongly suggests the document is designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://crysiq.ru/uplcv?utm_term=top+strategy+android+games PDF link annotation
    • http://otelm4b.ru/admin/ckfinder/userfiles/files/gifovanafevonolifuruse.pdfIn PDF document text
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613241837e8cf---37877544216.pdfIn PDF document text
    • https://elmaga.lt/components/com_mijoshop/opencart/image/data/files/vesibutejuvuguwuguxev.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/12tun6674a17tve9gjfk50fkt1/72423730776.pdfIn PDF document text
    • http://floridare.ru/app/webroot/img/uploads/file/241801_reregikiruka.pdfIn PDF document text
    • http://vytvarnyobchod.cz/UserFiles/File/95423710406.pdfIn PDF document text
    • https://grupahatak.pl/admin/_fck_files/file/navipawefonilubi.pdfIn PDF document text
    • https://mosaicopeoplecorporation.com/ckfinder/userfiles/files/8774380538.pdfIn PDF document text
    • http://zuszdounky.cz/files/diweraxage.pdfIn PDF document text
    • http://tl-maskinfabrik.dk/userfiles/file/sitesevexuvumoze.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16133719d8ca9c---buzoronukalomiv.pdfIn PDF document text
    • https://alusol-kw.com/ckfinder/userfiles/files/bawimitusen.pdfIn PDF document text
    • http://servmed.net/userfiles/file/jogogabasisobupilat.pdfIn PDF document text
    • http://15449010.com/FileData/ckfinder/files/20210915_91885BA2A1A7D133.pdfIn PDF document text
    • https://grup-insaat.com/userfiles/file/lomikomesonir.pdfIn PDF document text
    • http://christopherdallo.com/file/beguzixatasemix.pdfIn PDF document text
    • https://kcss.hu/korosi/userfiles/file/goxanun.pdfIn PDF document text
    • http://getdol.com/page_data/file/6710924117.pdfIn PDF document text
    • http://www.abcklima.hu/data/editorfile/rexifurumon.pdfIn PDF document text
    • https://cytairtool.com/test/userfiles/file/20210906_0c189.pdfIn PDF document text
    • https://khangle.vn/uploads/images/files/39690258818.pdfIn PDF document text
    • https://chameleoncoupons.com/adgprocessing/uploads/files/77502004591.pdfIn PDF document text
    • 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_off0000f355.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF355 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010b6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B6C 10768 bytes
SHA-256: 35ef08275069de202c636d131d23f2890237e5e780b7894d8b3f3d13a86feef6
font_02_sfnt_off00012403.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12403 16792 bytes
SHA-256: e7165b966f79f2a7151bcb99914798001efadf36d614cbf1daff99622f18fe7a